THE COMPLETE LIBRARY

All free calculators by category

1012 ways to make the numbers clearer. Search by name or choose a category.

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Percentage Calculator

Find what a percentage of a number amounts to.

Math & percentages↗

Percentage Change Calculator

Measure the percentage increase or decrease between two positive values.

Math & percentages↗

Percentage Difference Calculator

Compare two positive measurements without choosing one as the baseline.

Math & percentages↗

Reverse Percentage Calculator

Recover the original value before a percentage increase.

Math & percentages↗

Fraction to Decimal Calculator

Divide a numerator by a denominator to express a fraction as a decimal.

Math & percentages↗

Ratio Scaling Calculator

Scale the second part of a ratio when the first part changes.

Math & percentages↗

Square Root Calculator

Find the non-negative square root of a number.

Math & percentages↗

Exponent Calculator

Raise a positive base to a chosen exponent.

Math & percentages↗

Logarithm Calculator

Find the exponent needed to produce a number in a chosen base.

Math & percentages↗

Quadratic Discriminant Calculator

Check the discriminant of a quadratic equation to understand its real roots.

Math & percentages↗

Linear Equation Calculator

Solve ax + b = c for x.

Math & percentages↗

Arithmetic Sequence Calculator

Find a term in an arithmetic sequence with a fixed common difference.

Math & percentages↗

Geometric Sequence Calculator

Find a term in a sequence multiplied by a fixed ratio each step.

Math & percentages↗

Factorial Calculator

Calculate the product of all positive integers up to a whole number.

Math & percentages↗

Slope Calculator

Find the slope of a line between two points.

Math & percentages↗

Distance Between Points Calculator

Find the straight-line distance between two coordinates in a plane.

Geometry↗

Circle Area Calculator

Calculate the area enclosed by a circle from its radius.

Geometry↗

Circle Circumference Calculator

Find the distance around a circle using its radius.

Geometry↗

Rectangle Area Calculator

Find the area of a rectangle from its length and width.

Geometry↗

Rectangle Perimeter Calculator

Find the total length of the four sides of a rectangle.

Geometry↗

Triangle Area Calculator

Calculate a triangle’s area using a base and perpendicular height.

Geometry↗

Trapezoid Area Calculator

Find the area between a trapezoid’s parallel sides.

Geometry↗

Parallelogram Area Calculator

Calculate area from the base and perpendicular height of a parallelogram.

Geometry↗

Ellipse Area Calculator

Calculate the enclosed area of an ellipse using its two semi-axes.

Geometry↗

Pythagorean Theorem Calculator

Find the hypotenuse of a right triangle from its two shorter sides.

Geometry↗

Cuboid Volume Calculator

Calculate the volume of a rectangular box.

Geometry↗

Cylinder Volume Calculator

Calculate a right circular cylinder’s volume from radius and height.

Geometry↗

Cone Volume Calculator

Find a cone’s volume using its circular base radius and perpendicular height.

Geometry↗

Sphere Volume Calculator

Find the volume enclosed by a sphere from its radius.

Geometry↗

Sphere Surface Area Calculator

Calculate the outside surface area of a sphere.

Geometry↗

Cylinder Surface Area Calculator

Find the total surface area of a closed right circular cylinder.

Geometry↗

Sector Area Calculator

Calculate a circular sector’s area from radius and angle in degrees.

Geometry↗

Arc Length Calculator

Find the length of a circular arc from radius and central angle.

Geometry↗

Regular Polygon Interior Angle Calculator

Find each interior angle in a regular polygon.

Money & finance↗

Simple Interest Calculator

Estimate interest when it is calculated only on the original principal.

Money & finance↗

Compound Interest Calculator

Estimate a future balance with a fixed rate and regular compounding.

Money & finance↗

Loan Payment Calculator

Estimate a fixed monthly repayment for a fully amortising loan.

Money & finance↗

Mortgage Payment Calculator

Estimate principal-and-interest payments on a fixed-rate mortgage.

Money & finance↗

Savings Contribution Calculator

Find the monthly contribution needed to reach a savings target without interest.

Money & finance↗

Future Value of Monthly Deposits Calculator

Estimate the future value of equal end-of-month deposits.

Money & finance↗

Present Value Calculator

Discount a future payment into today’s equivalent value.

Money & finance↗

Investment Return Calculator

Calculate a simple return relative to the amount originally invested.

Money & finance↗

CAGR Calculator

Find a constant annual growth rate connecting a starting and ending value.

Money & finance↗

Inflation Future Cost Calculator

Estimate a future price using an annual inflation rate you choose.

Money & finance↗

Real Return Calculator

Adjust a nominal investment return for inflation.

Money & finance↗

Effective Annual Rate Calculator

Convert a nominal annual rate into an effective rate after compounding.

Money & finance↗

Debt to Income Calculator

Compare monthly debt payments with gross monthly income.

Money & finance↗

Savings Rate Calculator

Calculate what share of take-home income you save.

Money & finance↗

Emergency Fund Calculator

Estimate a savings target based on monthly essential expenses and months of cover.

Money & finance↗

Rule of 72 Calculator

Approximate how long a sum takes to double at a constant annual return.

Business & work↗

Profit Margin Calculator

Calculate gross profit as a percentage of revenue.

Business & work↗

Markup Calculator

Calculate how much a selling price exceeds cost as a percentage of cost.

Business & work↗

Selling Price Calculator

Find a selling price that achieves a chosen gross margin.

Business & work↗

Break Even Units Calculator

Estimate how many whole units cover fixed costs and variable unit costs.

Business & work↗

Revenue Calculator

Estimate sales revenue from unit price and quantity sold.

Business & work↗

Gross Profit Calculator

Calculate revenue left after cost of goods sold.

Business & work↗

Hourly Rate Calculator

Translate annual billable revenue needs into an hourly rate.

Business & work↗

Salary to Hourly Calculator

Convert gross annual salary to an hourly equivalent.

Business & work↗

Overtime Pay Calculator

Calculate overtime pay for a chosen number of hours and pay multiplier.

Business & work↗

Sales Commission Calculator

Estimate commission from eligible sales and a flat commission rate.

Business & work↗

Inventory Turnover Calculator

Measure how often average inventory is sold during a reporting period.

Business & work↗

Customer Acquisition Cost Calculator

Estimate acquisition spending per new customer.

Business & work↗

Conversion Rate Calculator

Find what percentage of visitors complete a chosen action.

Business & work↗

Cost Per Click Calculator

Calculate average advertising spend per click.

Business & work↗

Return on Ad Spend Calculator

Compare advertising-attributed revenue with advertising spend.

Business & work↗

Payback Period Calculator

Estimate recovery time for an initial outlay with equal annual net cash inflows.

Everyday life↗

Discount Calculator

Find a price after a single percentage discount.

Everyday life↗

Reverse Discount Calculator

Recover the original price from a discounted price and discount rate.

Everyday life↗

Tip Calculator

Calculate the tip amount from a bill and chosen percentage.

Everyday life↗

Split Bill Calculator

Split a bill and optional tip equally between a group.

Everyday life↗

Unit Price Calculator

Compare purchases by calculating their price per unit.

Everyday life↗

Reading Time Calculator

Estimate reading time from a word count and reading speed.

Everyday life↗

Download Time Calculator

Estimate the minimum time to download a decimal-megabyte file at a fixed speed.

Everyday life↗

Storage Capacity Calculator

Estimate how many equal-size files fit in decimal gigabytes of storage.

Everyday life↗

Screen Diagonal Calculator

Find a screen’s diagonal from its width and height.

Everyday life↗

Pixel Density Calculator

Calculate pixels per inch from resolution and physical screen diagonal.

Construction & DIY↗

Concrete Volume Calculator

Estimate wet concrete volume for a rectangular slab.

Construction & DIY↗

Paint Quantity Calculator

Estimate litres of paint for a net area and number of coats.

Construction & DIY↗

Tile Quantity Calculator

Estimate whole tiles for an area including a chosen waste allowance.

Construction & DIY↗

Flooring Packs Calculator

Estimate whole flooring packs for a room with an allowance for waste.

Construction & DIY↗

Brick Quantity Calculator

Estimate bricks for a net wall area using your brick-and-joint face dimensions.

Construction & DIY↗

Gravel Quantity Calculator

Estimate aggregate mass from area, depth and a supplied bulk density.

Construction & DIY↗

Wallpaper Rolls Calculator

Estimate wallpaper rolls using full-height strips and usable roll length.

Construction & DIY↗

Roof Pitch Calculator

Find a roof angle from its vertical rise and horizontal run.

Construction & DIY↗

Stair Riser Calculator

Find equal riser height from total rise and chosen number of risers.

Construction & DIY↗

Fence Post Calculator

Estimate posts for a straight open fence run with equal maximum spacing.

Construction & DIY↗

Board Feet Calculator

Calculate lumber volume in board feet from dimensions in inches and feet.

Construction & DIY↗

Pipe Internal Volume Calculator

Find internal pipe capacity from inner diameter and length.

Physics↗

Speed Calculator

Find average speed from total distance and elapsed time.

Physics↗

Acceleration Calculator

Find constant average acceleration from a change in velocity.

Physics↗

Force Calculator

Calculate net force using mass and acceleration.

Physics↗

Kinetic Energy Calculator

Find translational kinetic energy from mass and speed.

Physics↗

Potential Energy Calculator

Estimate gravitational potential energy relative to a reference height.

Physics↗

Momentum Calculator

Calculate linear momentum from mass and velocity.

Physics↗

Work Calculator

Find work done by a constant force along a displacement.

Physics↗

Mechanical Power Calculator

Calculate average power from work and elapsed time.

Physics↗

Pressure Calculator

Find uniform pressure from perpendicular force and contact area.

Physics↗

Density Calculator

Calculate average material density from mass and volume.

Physics↗

Frequency Calculator

Find frequency from the period of one repeating cycle.

Physics↗

Wave Speed Calculator

Calculate wave speed from frequency and wavelength.

Physics↗

Torque Calculator

Find torque magnitude for a force at an angle to a lever arm.

Physics↗

Free Fall Time Calculator

Estimate fall time from rest under constant gravity without air resistance.

Physics↗

Spring Force Calculator

Calculate force magnitude for an ideal spring under Hooke’s law.

Physics↗

Heat Energy Calculator

Estimate thermal energy for a temperature change without a phase change.

Electrical↗

Ohms Law Current Calculator

Calculate ideal DC current from voltage and resistance.

Electrical↗

Ohms Law Voltage Calculator

Find the voltage across an ideal resistor from current and resistance.

Electrical↗

Ohms Law Resistance Calculator

Find ideal electrical resistance from voltage and current.

Electrical↗

Electrical Power Calculator

Calculate DC electrical power from voltage and current.

Electrical↗

Resistor Power Calculator

Calculate power dissipated as heat in a resistor.

Electrical↗

Series Resistance Calculator

Add three resistors connected in series.

Electrical↗

Parallel Resistance Calculator

Find equivalent resistance for two positive resistors in parallel.

Electrical↗

Voltage Divider Calculator

Estimate unloaded output voltage from a two-resistor divider.

Electrical↗

Battery Energy Calculator

Convert nominal battery voltage and amp-hours into nominal energy.

Electrical↗

Battery Runtime Calculator

Estimate runtime from nominal battery energy, usable fraction and load power.

Electrical↗

Ideal Battery Charge Time Calculator

Estimate the minimum constant-current time to replace a chosen capacity.

Electrical↗

Capacitor Energy Calculator

Find stored energy in an ideal capacitor.

Chemistry↗

Moles Calculator

Convert a substance’s mass into amount of substance using its molar mass.

Chemistry↗

Molarity Calculator

Calculate solution molarity from solute amount and final solution volume.

Chemistry↗

Dilution Calculator

Find stock volume required for a target diluted concentration.

Chemistry↗

Mass Percent Calculator

Calculate a component’s mass percentage within a mixture.

Chemistry↗

Molality Calculator

Calculate molality using solute amount and solvent mass.

Chemistry↗

Ideal Gas Pressure Calculator

Estimate absolute pressure for an ideal gas in a specified volume.

Chemistry↗

Gas Density Calculator

Estimate ideal-gas density from absolute pressure, molar mass and temperature.

Chemistry↗

Molecule Count Calculator

Convert moles to a count of specified elementary entities.

Chemistry↗

Percent Yield Calculator

Compare actual product yield with theoretical yield.

Chemistry↗

Mass Concentration Calculator

Find solute mass per litre of final solution.

Fitness & sport↗

Running Pace Calculator

Calculate average running pace from distance and elapsed minutes.

Fitness & sport↗

Race Time Calculator

Estimate completion time at a chosen constant pace.

Fitness & sport↗

Running Speed Calculator

Convert a kilometre pace to average speed.

Fitness & sport↗

Cycling Cadence Speed Calculator

Estimate bicycle speed from cadence, gear ratio and wheel circumference.

Fitness & sport↗

Swimming Pace Calculator

Calculate average swim time per 100 metres.

Fitness & sport↗

Workout Volume Calculator

Calculate total lifted load for equal-weight repetitions across sets.

Fitness & sport↗

Step Distance Calculator

Estimate distance from step count and average step length.

Fitness & sport↗

Lap Count Calculator

Find the number of laps needed to reach a target distance.

Fitness & sport↗

Race Split Calculator

Find target time per equal-distance split at a constant pace.

Fitness & sport↗

Training Time Calculator

Add equal training sessions into a weekly time total.

Food & cooking↗

Recipe Scaling Calculator

Scale an ingredient amount to a new number of servings.

Food & cooking↗

Recipe Cost Per Serving Calculator

Divide total ingredient cost by the number of servings.

Food & cooking↗

Bakers Hydration Calculator

Calculate water mass as a percentage of flour mass in dough.

Food & cooking↗

Dough Water Calculator

Find water mass needed for a selected flour mass and hydration.

Food & cooking↗

Salt Bakers Percentage Calculator

Calculate salt as a baker’s percentage of flour mass.

Food & cooking↗

Coffee Ratio Calculator

Find brew-water mass for a chosen coffee-to-water ratio.

Food & cooking↗

Food Cost Percentage Calculator

Calculate ingredient cost as a share of a menu item’s selling price.

Food & cooking↗

Meal Portion Calculator

Divide a cooked batch equally into portions by weight.

Food & cooking↗

Brine Salt Calculator

Calculate salt mass from water mass and a water-based salt percentage.

Food & cooking↗

Recipe Pan Scaling Calculator

Scale a round-pan recipe by area while keeping approximately the same depth.

Travel & motoring↗

Journey Time Calculator

Estimate moving time from distance and average speed.

Travel & motoring↗

Fuel Cost Calculator

Estimate fuel spending from trip distance, consumption and fuel price.

Travel & motoring↗

Fuel Consumption Calculator

Find litres used per 100 kilometres travelled.

Travel & motoring↗

Fuel Range Calculator

Estimate range from usable fuel and average consumption.

Travel & motoring↗

Travel Budget Calculator

Estimate total travel cost from daily spending, duration and fixed expenses.

Travel & motoring↗

Carpool Cost Calculator

Split journey fuel spending equally across travellers.

Travel & motoring↗

EV Charging Time Calculator

Estimate charging time for an energy amount at a constant effective charging power.

Travel & motoring↗

EV Journey Energy Calculator

Estimate electricity used over a trip at a chosen consumption rate.

Travel & motoring↗

EV Charging Cost Calculator

Estimate the electricity cost for adding energy to a vehicle battery.

Travel & motoring↗

Miles Per Gallon UK Calculator

Calculate fuel economy using imperial gallons and miles.

Travel & motoring↗

Miles Per Gallon US Calculator

Calculate fuel economy using US liquid gallons and miles.

Travel & motoring↗

Trip Average Speed Calculator

Calculate overall trip speed including time stopped.

Statistics↗

Arithmetic Mean Calculator

Find the arithmetic mean of a variable-length list of numbers.

Statistics↗

Weighted Mean Calculator

Combine three values using non-negative weights.

Statistics↗

Median Calculator

Find the median of a variable-length numeric dataset.

Statistics↗

Data Range Calculator

Find the difference between the largest and smallest values in a dataset.

Statistics↗

Population Standard Deviation Calculator

Find population standard deviation from a list of numeric observations.

Statistics↗

Sample Standard Deviation Calculator

Estimate sample standard deviation from a variable-length numeric list.

Statistics↗

Z Score Calculator

Express a value’s distance from the mean in standard deviations.

Statistics↗

Standard Error Calculator

Estimate the standard error of a sample mean.

Statistics↗

Independent Events Probability Calculator

Find the probability that two independent events both occur.

Statistics↗

At Least One Event Calculator

Calculate the probability of at least one success in independent identical trials.

Statistics↗

Coefficient of Variation Calculator

Express a standard deviation relative to a positive mean.

Statistics↗

Relative Error Calculator

Compare absolute measurement error with a positive reference value.

Energy & environment↗

Appliance Energy Calculator

Estimate electricity consumption from appliance power and operating hours.

Energy & environment↗

Electricity Cost Calculator

Calculate energy charges from consumption and a manually entered unit rate.

Energy & environment↗

Solar Output Calculator

Estimate solar energy from rated capacity, equivalent full-sun hours and a system factor.

Energy & environment↗

Water Use Calculator

Estimate water use for repeated timed activities such as showers.

Energy & environment↗

Rainwater Collection Calculator

Estimate collected water from rainfall, roof area and a runoff factor.

Energy & environment↗

Carbon Emissions Calculator

Estimate emissions from activity multiplied by a chosen emission factor.

Energy & environment↗

LED Savings Calculator

Estimate energy savings from replacing equal-use lighting with lower-wattage bulbs.

Energy & environment↗

Energy Payback Calculator

Estimate simple payback time for an efficiency upgrade.

Energy & environment↗

Heating Energy Calculator

Estimate ideal energy required to raise water temperature.

Energy & environment↗

Waste Diversion Calculator

Calculate the share of waste sent to recycling or reuse instead of disposal.

Unit converters↗

Metres to Feet Converter

Convert metres to feet with an explicit conversion factor.

Unit converters↗

Feet to Metres Converter

Convert feet to metres with an explicit conversion factor.

Unit converters↗

Inches to Centimetres Converter

Convert inches to cm with an explicit conversion factor.

Unit converters↗

Centimetres to Inches Converter

Convert cm to inches with an explicit conversion factor.

Unit converters↗

Kilometres to Miles Converter

Convert km to miles with an explicit conversion factor.

Unit converters↗

Miles to Kilometres Converter

Convert miles to km with an explicit conversion factor.

Unit converters↗

Kilograms to Pounds Converter

Convert kg to lb with an explicit conversion factor.

Unit converters↗

Pounds to Kilograms Converter

Convert lb to kg with an explicit conversion factor.

Unit converters↗

Grams to Ounces Converter

Convert g to oz with an explicit conversion factor.

Unit converters↗

Ounces to Grams Converter

Convert oz to g with an explicit conversion factor.

Unit converters↗

Litres to US Gallons Converter

Convert L to US gal with an explicit conversion factor.

Unit converters↗

Litres to UK Gallons Converter

Convert L to UK gal with an explicit conversion factor.

Unit converters↗

US Gallons to Litres Converter

Convert US gal to L with an explicit conversion factor.

Unit converters↗

UK Gallons to Litres Converter

Convert UK gal to L with an explicit conversion factor.

Unit converters↗

Square Feet to Square Metres Converter

Convert sq ft to m² with an explicit conversion factor.

Unit converters↗

Square Metres to Square Feet Converter

Convert m² to sq ft with an explicit conversion factor.

Unit converters↗

Acres to Hectares Converter

Convert acres to ha with an explicit conversion factor.

Unit converters↗

Hectares to Acres Converter

Convert ha to acres with an explicit conversion factor.

Unit converters↗

Kilometres Per Hour to Metres Per Second Converter

Convert km/h to m/s with an explicit conversion factor.

Unit converters↗

Metres Per Second to Kilometres Per Hour Converter

Convert m/s to km/h with an explicit conversion factor.

Unit converters↗

Miles Per Hour to Kilometres Per Hour Converter

Convert mph to km/h with an explicit conversion factor.

Unit converters↗

Kilometres Per Hour to Miles Per Hour Converter

Convert km/h to mph with an explicit conversion factor.

Unit converters↗

Kilowatt Hours to Joules Converter

Convert kWh to J with an explicit conversion factor.

Unit converters↗

Joules to Kilowatt Hours Converter

Convert J to kWh with an explicit conversion factor.

Unit converters↗

Bar to Pascals Converter

Convert bar to Pa with an explicit conversion factor.

Unit converters↗

Pascals to Bar Converter

Convert Pa to bar with an explicit conversion factor.

Unit converters↗

Minutes to Hours Converter

Convert minutes to hours with an explicit conversion factor.

Unit converters↗

Hours to Minutes Converter

Convert hours to minutes with an explicit conversion factor.

Unit converters↗

Radians to Degrees Converter

Convert radians to degrees with an explicit conversion factor.

Unit converters↗

Degrees to Radians Converter

Convert degrees to radians with an explicit conversion factor.

Unit converters↗

Celsius to Fahrenheit Converter

Convert a temperature on the Celsius scale to Fahrenheit.

Unit converters↗

Fahrenheit to Celsius Converter

Convert Fahrenheit temperature readings to Celsius.

Unit converters↗

Celsius to Kelvin Converter

Convert a Celsius temperature to absolute temperature in kelvins.

Unit converters↗

Kelvin to Celsius Converter

Convert absolute temperature in kelvins to Celsius.

Math & percentages↗

Percentage Point Calculator

Find the percentage-point difference between two rates.

Math & percentages↗

Weighted Percentage Calculator

Combine two percentages using their actual group sizes.

Math & percentages↗

Successive Discounts Calculator

Calculate the final price after two discounts applied one after the other.

Math & percentages↗

Percentage Composition Calculator

Find one component’s percentage of the sum of three components.

Math & percentages↗

Nth Root Calculator

Find the positive nth root of a non-negative number.

Math & percentages↗

Natural Log Calculator

Calculate the logarithm of a positive number to base e.

Math & percentages↗

Arithmetic Series Sum Calculator

Add the first n terms of an arithmetic sequence.

Math & percentages↗

Geometric Series Sum Calculator

Add a finite sequence that changes by a constant multiplier.

Math & percentages↗

Doubling Time Calculator

Find exact doubling time under a fixed effective growth rate per period.

Math & percentages↗

Exponential Decay Calculator

Estimate what remains after repeated percentage reductions.

Math & percentages↗

Greatest Common Divisor Calculator

Find the greatest positive integer that divides two whole numbers.

Math & percentages↗

Least Common Multiple Calculator

Find the smallest positive whole number divisible by two positive integers.

Math & percentages↗

Combination Calculator

Count ways to choose k items from n when order does not matter.

Math & percentages↗

Permutation Calculator

Count ordered selections without replacement.

Math & percentages↗

Sine Calculator

Find the sine of an angle entered in degrees.

Math & percentages↗

Cosine Calculator

Find the cosine of an angle entered in degrees.

Math & percentages↗

Tangent Calculator

Find the tangent of an angle in degrees away from vertical asymptotes.

Math & percentages↗

Arcsine Calculator

Find the principal angle whose sine equals a chosen ratio.

Math & percentages↗

Arccosine Calculator

Find the principal angle whose cosine equals a chosen ratio.

Math & percentages↗

Arctangent Calculator

Find the principal angle corresponding to a tangent ratio.

Math & percentages↗

Law of Cosines Calculator

Find a triangle’s third side from two sides and their included angle.

Math & percentages↗

Law of Sines Side Calculator

Find a triangle side using two known opposite angle-side relationships.

Geometry↗

Herons Formula Calculator

Find triangle area when all three side lengths are known.

Geometry↗

Equilateral Triangle Area Calculator

Find the area of a triangle with three equal sides.

Geometry↗

Triangle Perimeter Calculator

Add the side lengths of a valid triangle.

Geometry↗

Right Triangle Leg Calculator

Recover a right triangle’s missing leg from the hypotenuse and another leg.

Geometry↗

Annulus Area Calculator

Find the area of a ring between two concentric circles.

Geometry↗

Circle Segment Area Calculator

Calculate the smaller circular segment cut off by a chord.

Geometry↗

Chord Length Calculator

Find the straight chord connecting two points on a circle.

Geometry↗

Regular Polygon Area Calculator

Find the area of a regular polygon from side count and side length.

Geometry↗

Rhombus Area Calculator

Find a rhombus area using its diagonals.

Geometry↗

Kite Area Calculator

Find the area of a simple kite from its perpendicular diagonals.

Geometry↗

Cube Surface Area Calculator

Find the total outside area of a cube.

Geometry↗

Cuboid Surface Area Calculator

Find the combined area of all six faces of a rectangular box.

Geometry↗

Pyramid Volume Calculator

Find the volume of a pyramid from its base area and perpendicular height.

Geometry↗

Cone Slant Height Calculator

Calculate the side length from base rim to tip of a right circular cone.

Geometry↗

Cone Surface Area Calculator

Find a right circular cone’s base and curved area combined.

Geometry↗

Conical Frustum Volume Calculator

Find the volume of a cone with its pointed top removed.

Geometry↗

Ellipsoid Volume Calculator

Find ellipsoid volume from its three perpendicular semi-axes.

Geometry↗

Torus Volume Calculator

Calculate the volume of a ring-shaped torus.

Geometry↗

Three Dimensional Distance Calculator

Find the straight distance between two points in three-dimensional space.

Geometry↗

Vector Dot Product Calculator

Calculate the dot product of two three-component vectors.

Money & finance↗

Savings Goal Time Calculator

Find how many whole months of fixed contributions reach a savings goal without interest.

Money & finance↗

Savings Interest Earned Calculator

Separate interest earned from the principal in a fixed-rate annual-compounding model.

Money & finance↗

Continuous Compounding Calculator

Estimate a balance when nominal interest compounds continuously.

Money & finance↗

Loan Total Interest Calculator

Estimate total interest on a fixed-rate monthly amortising loan.

Money & finance↗

Interest Only Loan Calculator

Find monthly interest for a loan whose principal is not reduced by regular payments.

Money & finance↗

Loan Affordability Calculator

Find the loan principal supported by a chosen fixed monthly payment.

Money & finance↗

Loan to Value Calculator

Compare secured borrowing with the property value supporting it.

Money & finance↗

Home Equity Calculator

Estimate property equity before sale costs by subtracting secured debt.

Money & finance↗

Rental Yield Calculator

Calculate gross annual rent as a percentage of property purchase price.

Money & finance↗

Net Rental Yield Calculator

Estimate rental yield after entered annual operating expenses.

Money & finance↗

Down Payment Calculator

Calculate a property deposit amount from a chosen percentage of price.

Money & finance↗

Capital Gains Return Calculator

Find absolute gain after subtracting entered purchase and selling costs.

Money & finance↗

Dividend Yield Calculator

Compare annual dividend per share with current share price.

Money & finance↗

Portfolio Weight Calculator

Calculate an asset’s percentage of a portfolio total.

Money & finance↗

Bond Current Yield Calculator

Calculate annual coupon income relative to a bond market price.

Money & finance↗

Expense Ratio Cost Calculator

Estimate annual fund fees from a constant assumed balance and expense ratio.

Money & finance↗

Sinking Fund Calculator

Find a regular monthly amount for a known future expense without interest.

Business & work↗

Contribution Margin Calculator

Find the contribution per unit after variable costs.

Business & work↗

Contribution Margin Ratio Calculator

Express contribution as a share of unit selling price.

Business & work↗

Break Even Revenue Calculator

Estimate sales revenue needed to cover fixed costs at a chosen contribution ratio.

Business & work↗

Target Profit Units Calculator

Find whole units needed to cover fixed costs and a chosen operating profit target.

Business & work↗

Margin of Safety Calculator

Find how far revenue exceeds break-even sales as a share of revenue.

Business & work↗

Operating Margin Calculator

Calculate operating profit as a percentage of revenue.

Business & work↗

Net Profit Margin Calculator

Calculate the share of revenue left as net profit.

Business & work↗

Working Capital Calculator

Subtract current liabilities from current assets.

Business & work↗

Current Ratio Calculator

Compare current assets with current liabilities.

Business & work↗

Quick Ratio Calculator

Compare liquid current assets with current liabilities, excluding inventory.

Business & work↗

Customer Churn Rate Calculator

Calculate customers lost as a percentage of the starting customer base.

Business & work↗

Customer Retention Rate Calculator

Estimate retained starting customers after excluding customers acquired during the period.

Business & work↗

Average Order Value Calculator

Find mean revenue per order.

Business & work↗

Email Click Through Rate Calculator

Find unique email clicks as a share of successfully delivered emails.

Business & work↗

CPM Calculator

Calculate advertising cost per thousand impressions.

Business & work↗

Cost Per Acquisition Calculator

Calculate advertising cost for each recorded conversion.

Business & work↗

Capacity Utilisation Calculator

Compare actual output with available output capacity.

Business & work↗

Labour Productivity Calculator

Find output per labour hour.

Business & work↗

Inventory Days Calculator

Convert inventory turnover into approximate days held.

Business & work↗

Cash Runway Calculator

Estimate months before cash is exhausted under a constant net monthly cash burn.

Physics↗

Constant Acceleration Distance Calculator

Find displacement from initial velocity, time and constant acceleration.

Physics↗

Final Velocity Calculator

Calculate velocity after a period of constant acceleration.

Physics↗

Stopping Distance Calculator

Find ideal braking distance from speed and a constant deceleration magnitude.

Physics↗

Reaction Distance Calculator

Find distance travelled at constant speed during a reaction delay.

Physics↗

Projectile Range Calculator

Find horizontal range for a projectile landing at its launch height without drag.

Physics↗

Projectile Maximum Height Calculator

Estimate rise above launch height in ideal projectile motion.

Physics↗

Centripetal Acceleration Calculator

Calculate inward acceleration for uniform circular motion.

Physics↗

Centripetal Force Calculator

Find net inward force needed for uniform circular motion.

Physics↗

Angular Velocity Calculator

Convert rotations per minute into angular velocity.

Physics↗

Tangential Speed Calculator

Find linear speed at a radius on a rotating object.

Physics↗

Impulse Calculator

Calculate impulse from a constant net force over a time interval.

Physics↗

Friction Force Calculator

Estimate sliding friction magnitude using coefficient and normal force.

Physics↗

Spring Energy Calculator

Find elastic energy stored in a linear spring.

Physics↗

Mechanical Efficiency Calculator

Compare useful output energy with input energy.

Physics↗

Hydrostatic Pressure Calculator

Find gauge pressure caused by a liquid column.

Physics↗

Buoyant Force Calculator

Find buoyancy from displaced fluid volume and density.

Physics↗

Volumetric Flow Rate Calculator

Calculate volumetric flow from cross-sectional area and average velocity.

Physics↗

Mass Flow Rate Calculator

Calculate mass flow from fluid density and volumetric flow.

Physics↗

Reynolds Number Calculator

Calculate the dimensionless Reynolds number for a chosen characteristic length.

Physics↗

Thermal Expansion Calculator

Estimate length change using a constant linear expansion coefficient.

Physics↗

Heat Conduction Calculator

Find steady heat-transfer power through a uniform flat layer.

Physics↗

Latent Heat Calculator

Calculate energy for a phase change at constant temperature.

Physics↗

Pendulum Period Calculator

Estimate the period of a simple pendulum for small oscillations.

Physics↗

Spring Oscillation Period Calculator

Estimate oscillation period for an ideal mass on a linear spring.

Electrical↗

Series Capacitance Calculator

Find the equivalent capacitance of two ideal capacitors in series.

Electrical↗

Parallel Capacitance Calculator

Add capacitances of two ideal parallel capacitors.

Electrical↗

RC Time Constant Calculator

Calculate a resistor-capacitor circuit’s time constant.

Electrical↗

RL Time Constant Calculator

Calculate the time constant of an ideal series resistor-inductor circuit.

Electrical↗

Capacitive Reactance Calculator

Find capacitor reactance magnitude at a given sinusoidal frequency.

Electrical↗

Inductive Reactance Calculator

Find ideal inductor reactance magnitude for sinusoidal AC.

Electrical↗

LC Resonant Frequency Calculator

Find the ideal natural resonant frequency of an LC circuit.

Electrical↗

AC Apparent Power Calculator

Calculate apparent power from single-phase RMS voltage and current.

Electrical↗

Power Factor Calculator

Calculate real power divided by apparent power.

Electrical↗

Three Phase Power Calculator

Estimate balanced three-phase real power from line voltage and line current.

Electrical↗

RMS Sine Voltage Calculator

Convert peak amplitude of a pure sine wave to RMS voltage.

Electrical↗

LED Series Resistor Calculator

Estimate resistance for a single LED from source voltage, forward drop and current.

Electrical↗

Transformer Voltage Calculator

Find ideal secondary voltage from primary voltage and turns ratio.

Electrical↗

Voltage Drop DC Calculator

Estimate resistive voltage drop using current and total loop resistance.

Chemistry↗

Solution Mass Calculator

Find solute mass needed for a chosen molarity and final solution volume.

Chemistry↗

Mole Fraction Calculator

Find a component’s mole fraction in a two-component mixture.

Chemistry↗

Solution Mixing Calculator

Estimate concentration after mixing two solutions with additive volumes.

Chemistry↗

Parts Per Million Calculator

Calculate mass-based ppm from solute and total mixture masses.

Chemistry↗

Boyles Law Calculator

Find final volume for an ideal gas at constant temperature and fixed amount.

Chemistry↗

Charles Law Calculator

Find final gas volume after a temperature change at fixed absolute pressure.

Chemistry↗

Combined Gas Law Calculator

Find final volume when ideal-gas pressure and temperature both change.

Chemistry↗

Theoretical Yield Calculator

Calculate theoretical product mass from reactant mass and a molar stoichiometric ratio.

Chemistry↗

Atom Economy Calculator

Find theoretical desired-product mass relative to reactant mass in a balanced equation.

Chemistry↗

Percent Purity Calculator

Calculate a sample’s pure-component mass as a percentage of total sample mass.

Statistics↗

Binomial Probability Calculator

Find the probability of exactly k successes in n independent identical trials.

Statistics↗

Poisson Probability Calculator

Find the probability of a specific event count under a Poisson model.

Statistics↗

Binomial Mean Calculator

Find the expected number of successes across identical independent trials.

Statistics↗

Binomial Standard Deviation Calculator

Find the standard deviation of the success count in a binomial model.

Statistics↗

Expected Monetary Value Calculator

Combine two mutually exclusive outcomes using a chosen probability.

Statistics↗

Bayes Theorem Calculator

Update a prior probability using likelihoods for evidence under two alternatives.

Statistics↗

Proportion Standard Error Calculator

Estimate the standard error of a sample proportion under a simple independent-sampling model.

Statistics↗

Normal Confidence Interval Margin Calculator

Calculate the margin around a mean from a supplied z critical value.

Statistics↗

Sample Size for a Proportion Calculator

Estimate a normal-approximation sample size for a target proportion margin.

Statistics↗

Root Mean Square Calculator

Calculate RMS for four equally weighted observations.

Statistics↗

Geometric Mean Calculator

Find the geometric mean of three positive values.

Statistics↗

Harmonic Mean Calculator

Find the harmonic mean of two positive values.

Statistics↗

Pooled Standard Deviation Calculator

Combine two sample deviations under a common-variance assumption.

Statistics↗

Cohens D Calculator

Calculate a mean difference standardised by a supplied pooled deviation.

Statistics↗

Uniform Distribution Probability Calculator

Find probability over an interval within a continuous uniform distribution.

Statistics↗

Exponential Survival Probability Calculator

Find the probability of waiting longer than a chosen time in an exponential model.

Computing & digital↗

Image File Size Calculator

Estimate uncompressed image pixel-data size from resolution and colour depth.

Computing & digital↗

Video File Size Calculator

Estimate encoded video-stream size from average bitrate and duration.

Computing & digital↗

Audio File Size Calculator

Estimate uncompressed PCM audio data from sample rate, depth, channels and duration.

Computing & digital↗

Video Bitrate Calculator

Find a target total average bitrate from desired file size and duration.

Computing & digital↗

Aspect Ratio Calculator

Calculate width-to-height ratio as a decimal.

Computing & digital↗

Aspect Ratio Height Calculator

Find a proportional height for a chosen width and target aspect ratio.

Computing & digital↗

Image Print Width Calculator

Find physical print width from horizontal pixels and pixels per inch.

Computing & digital↗

Megapixel Calculator

Find total pixel count in megapixels from image dimensions.

Computing & digital↗

Data Transfer Cost Calculator

Estimate data egress charges from decimal gigabytes and a manually entered rate.

Computing & digital↗

Backup Storage Calculator

Estimate storage for retained full backups with an assumed compression ratio.

Computing & digital↗

Compression Ratio Calculator

Compare original size with compressed size as a compression multiple.

Computing & digital↗

Storage Saving Percentage Calculator

Find the percentage of original data size saved after compression.

Computing & digital↗

Required Bandwidth Calculator

Estimate aggregate link capacity for concurrent streams at a chosen utilisation ceiling.

Computing & digital↗

Network Throughput Calculator

Find average data throughput from decimal megabytes and elapsed time.

Computing & digital↗

Packet Serialization Delay Calculator

Estimate time to transmit a packet’s bits onto a link.

Computing & digital↗

Availability Downtime Calculator

Translate an availability percentage into downtime over a chosen period.

Computing & digital↗

Requests Per Second Calculator

Calculate average request rate over a measurement window.

Computing & digital↗

Little Law Concurrency Calculator

Estimate average items in a stable system from arrival rate and average time.

Computing & digital↗

Binary Address Space Calculator

Count distinct combinations represented by a fixed number of bits.

Computing & digital↗

Frame Count Calculator

Find frame count from constant frame rate and duration.

Astronomy & space↗

Kepler Orbital Period Calculator

Estimate a small body’s orbital period around a one-solar-mass star.

Astronomy & space↗

Circular Orbit Speed Calculator

Find ideal circular orbital speed around a body using its gravitational parameter.

Astronomy & space↗

Escape Velocity Calculator

Find ideal escape speed from a spherical body at a chosen centre distance.

Astronomy & space↗

Telescope Magnification Calculator

Find telescope magnification from telescope and eyepiece focal lengths.

Astronomy & space↗

Telescope Exit Pupil Calculator

Calculate the diameter of light leaving a telescope eyepiece.

Astronomy & space↗

Telescope Focal Ratio Calculator

Calculate optical focal ratio from focal length and aperture.

Astronomy & space↗

Angular Size Calculator

Find apparent angular diameter from physical size and distance.

Astronomy & space↗

Light Travel Time Calculator

Find time for light to travel a vacuum distance expressed in kilometres.

Astronomy & space↗

Parallax Distance Calculator

Estimate stellar distance from annual parallax angle in arcseconds.

Astronomy & space↗

Distance Modulus Calculator

Find distance modulus from a distance expressed in parsecs.

Education & study↗

Test Grade Percentage Calculator

Convert earned marks into a percentage of available marks.

Education & study↗

Final Exam Grade Needed Calculator

Find the exam percentage required to reach a chosen course target.

Education & study↗

Course Weighted Grade Calculator

Combine coursework and exam grades with a chosen exam weight.

Education & study↗

GPA Calculator

Calculate a credit-weighted GPA from matching lists of grade points and course credits.

Education & study↗

Cumulative GPA Calculator

Combine existing GPA credits with a new term’s GPA and credits.

Education & study↗

Required Average Grade Calculator

Find the average percentage needed on remaining equally weighted assessments.

Education & study↗

Study Schedule Calculator

Divide a fixed amount of study time across available days.

Education & study↗

Exam Time Per Question Calculator

Estimate time per equally weighted question after reserving review time.

Education & study↗

Attendance Percentage Calculator

Calculate attended sessions as a percentage of scheduled sessions.

Education & study↗

Attendance Target Calculator

Find extra fully attended sessions needed to reach a chosen attendance percentage.

Everyday life↗

Time Duration Calculator

Find elapsed minutes between start and end times on a 24-hour clock.

Everyday life↗

Work Hours Calculator

Find paid hours from gross shift duration after an unpaid break.

Everyday life↗

Weekly Hours Calculator

Estimate weekly hours from equal daily hours and days worked.

Everyday life↗

Speaking Time Calculator

Estimate delivery time from script length and a chosen speaking rate.

Everyday life↗

Rent Split by Income Calculator

Allocate one person’s share of rent in proportion to two incomes.

Everyday life↗

Monthly to Annual Cost Calculator

Translate a recurring monthly payment into an annual total.

Everyday life↗

Subscription Cost Per Use Calculator

Estimate cost per use of a subscription during one billing period.

Everyday life↗

Shared Utility Split Calculator

Allocate a utility bill between equal shares and a chosen personal adjustment.

Everyday life↗

Buy Versus Rent Break Even Calculator

Find whole rental uses needed to equal a purchase cost under simple fixed-cost assumptions.

Everyday life↗

Multi Buy Unit Cost Calculator

Calculate the effective unit price of a fixed-price multi-buy offer.

Construction & DIY↗

Topsoil Volume Calculator

Find uncompacted topsoil volume from garden area and desired depth.

Construction & DIY↗

Mulch Volume Calculator

Estimate mulch volume for a circular planting bed excluding a central unmulched area.

Construction & DIY↗

Sand Mass Calculator

Convert required sand volume to estimated mass using a supplied bulk density.

Construction & DIY↗

Bagged Material Calculator

Find whole bags needed to cover a required quantity in the same units as each bag.

Construction & DIY↗

Ramp Slope Calculator

Calculate ramp gradient as rise over horizontal run.

Construction & DIY↗

Ramp Length Calculator

Calculate inclined ramp length from vertical rise and horizontal run.

Construction & DIY↗

Diagonal Square Check Calculator

Find the expected diagonal of a rectangular frame from its side dimensions.

Construction & DIY↗

Paver Quantity Calculator

Estimate rectangular pavers for an area using paver dimensions plus joint width.

Construction & DIY↗

Rectangular Pond Capacity Calculator

Estimate a rectangular pond’s gross water capacity from internal dimensions.

Construction & DIY↗

Cylindrical Tank Capacity Calculator

Calculate liquid volume in a vertical cylinder at a chosen water depth.

Food & cooking↗

Pizza Dough Ball Calculator

Find equal dough-ball mass after a chosen allowance for handling loss.

Food & cooking↗

Dough Yield Calculator

Find dough mass from flour mass and summed baker’s percentages of other ingredients.

Food & cooking↗

Sourdough Starter Flour Calculator

Separate flour mass within starter from total starter weight and hydration.

Food & cooking↗

Round Cake Servings Calculator

Estimate equal portions from round cake area and chosen serving area.

Food & cooking↗

Cooking Weight Loss Calculator

Measure mass lost between raw and cooked food.

Food & cooking↗

Edible Portion Yield Calculator

Find usable food weight after a chosen trimming or preparation loss.

Food & cooking↗

Ingredient Purchase Quantity Calculator

Work backwards from required edible weight to purchase weight.

Food & cooking↗

Batch Selling Price Calculator

Find batch selling revenue needed to reach a chosen gross margin on entered batch costs.

Fitness & sport↗

Walking Time Calculator

Estimate walking time for a chosen distance and average speed.

Fitness & sport↗

Rowing Split Calculator

Calculate average rowing time per 500 metres from total time and distance.

Fitness & sport↗

Track Lap Split Calculator

Find target time per lap from goal duration and race distance.

Fitness & sport↗

Interval Workout Time Calculator

Add work intervals, between-interval rests and warm-up/cool-down time.

Fitness & sport↗

Training Load Ratio Calculator

Compare this week’s load with a manually supplied recent weekly average.

Fitness & sport↗

Race Percentage Improvement Calculator

Measure the relative reduction in elapsed race time.

Travel & motoring↗

Fuel Cost Per Kilometre Calculator

Translate consumption and fuel price into a distance-based fuel cost.

Travel & motoring↗

Fuel Cost Savings Calculator

Compare fuel spending before and after a change in consumption.

Travel & motoring↗

EV Cost Per Kilometre Calculator

Estimate grid electricity cost per kilometre including chosen charging losses.

Travel & motoring↗

EV Range Calculator

Estimate distance from usable battery energy and a chosen driving consumption.

Travel & motoring↗

Trip Cost With Tolls Calculator

Add fuel, tolls and parking for one planned trip.

Travel & motoring↗

Travel Cost Per Day Calculator

Allocate total trip spending across the number of travel days.

Travel & motoring↗

Route Time Saving Calculator

Compare two travel times for the same distance at different average speeds.

Travel & motoring↗

Average Speed for Equal Distances Calculator

Find average speed for two equal-distance legs at different speeds.

Energy & environment↗

Electricity Bill Calculator

Combine metered energy charges and a fixed daily charge.

Energy & environment↗

Appliance Annual Cost Calculator

Estimate annual electricity spending for a constant-power appliance.

Energy & environment↗

Standby Power Cost Calculator

Estimate annual electricity cost for a load left continuously in standby.

Energy & environment↗

Solar Self Consumption Calculator

Find the share of generated solar electricity used directly on site.

Energy & environment↗

Solar Self Sufficiency Calculator

Find the share of total site demand met by on-site solar energy.

Energy & environment↗

Solar Export Revenue Calculator

Estimate revenue from exported electricity at a manually entered flat rate.

Energy & environment↗

Solar Annual Value Calculator

Combine avoided import spending and export income for a solar scenario.

Energy & environment↗

Water Bill Calculator

Estimate water charges from a volume-based rate and a fixed period charge.

Energy & environment↗

Shower Water Saving Calculator

Compare water use before and after reducing flow rate for repeated showers.

Energy & environment↗

Leak Water Loss Calculator

Estimate water lost through a continuous measured leak.

Physics↗

Mechanical Advantage Calculator

Compare output force with input force for a simple machine.

Math & percentages↗

Scientific Calculator

Evaluate arithmetic, powers, parentheses and common scientific functions.

Math & percentages↗

Basic Calculator

Evaluate everyday arithmetic with brackets and standard operation precedence.

Math & percentages↗

Fraction Calculator

Add, subtract, multiply or divide two fractions and simplify the answer.

Math & percentages↗

Simplify Fraction Calculator

Reduce an integer fraction to its lowest terms.

Math & percentages↗

Mixed Number to Improper Fraction Calculator

Convert a non-negative mixed number to a simplified improper fraction.

Math & percentages↗

Improper Fraction to Mixed Number Calculator

Express a non-negative improper fraction as a whole part and remainder.

Math & percentages↗

Compare Fractions Calculator

Compare two fractions by exact integer cross products within the input limits.

Math & percentages↗

Decimal to Fraction Calculator

Convert a finite decimal string into a reduced fraction.

Math & percentages↗

Scientific Notation Calculator

Express a finite number in standard coefficient-times-power-of-ten notation.

Math & percentages↗

Significant Figures Rounding Calculator

Round a numeric value to a specified number of significant digits.

Math & percentages↗

Prime Factorization Calculator

Decompose a positive integer into its prime factors.

Math & percentages↗

Factor Calculator

List all positive integer divisors of a whole number.

Math & percentages↗

Prime Number Checker

Check whether an integer is prime using exact trial division within the supported range.

Math & percentages↗

Roman Numeral Calculator

Convert an integer to canonical Roman numerals.

Math & percentages↗

Roman Numeral to Number Calculator

Convert a canonical Roman numeral into an integer.

Math & percentages↗

Binary to Decimal Calculator

Convert an unsigned binary integer to decimal.

Math & percentages↗

Decimal to Binary Calculator

Convert a non-negative decimal integer to binary notation.

Math & percentages↗

Hexadecimal to Decimal Calculator

Convert an unsigned hexadecimal integer to decimal.

Math & percentages↗

Decimal to Hexadecimal Calculator

Convert an unsigned decimal integer to hexadecimal.

Date & time↗

Age Calculator

Find completed years of age between a birth date and an as-of date.

Date & time↗

Date Difference Calculator

Count calendar days from a start date to an end date.

Date & time↗

Add Days to Date Calculator

Find the calendar date a chosen whole number of days after or before another date.

Date & time↗

Business Days Calculator

Count Monday-to-Friday dates in a start-inclusive, end-exclusive interval.

Date & time↗

Add Business Days Calculator

Move a date by a signed number of Monday-to-Friday working days.

Date & time↗

Day of the Week Calculator

Find the weekday name for a Gregorian calendar date.

Date & time↗

ISO Week Number Calculator

Find ISO week-year and week number for a chosen date.

Date & time↗

Days in Month Calculator

Find the number of days in a Gregorian month, including leap-year February.

Date & time↗

Day of Year Calculator

Find the ordinal position of a date within its Gregorian year.

Date & time↗

Age in Days Calculator

Count complete calendar days between a birth date and an as-of date.

Date & time↗

Weeks Between Dates Calculator

Express a signed calendar-day interval as decimal weeks.

Date & time↗

Year Progress Calculator

Find the percentage of calendar dates elapsed at the start of a chosen date.

Date & time↗

Anniversary Year Calculator

Find the anniversary calendar year from an original year and a selected anniversary number.

Statistics↗

Statistics Calculator

Summarise a numeric dataset with its count, mean, median, minimum and maximum.

Statistics↗

Mode Calculator

Find the most frequent value or tied values in a numeric dataset.

Statistics↗

Percentile Calculator

Find a dataset percentile using inclusive linear interpolation.

Statistics↗

Interquartile Range Calculator

Measure the spread of the middle half of a dataset.

Statistics↗

Percentile Rank Calculator

Find the percentage of supplied observations strictly below a chosen value.

Statistics↗

Population Variance Calculator

Find population variance for a variable-length numeric dataset.

Statistics↗

Sample Variance Calculator

Estimate variance using N minus one for a supplied sample.

Statistics↗

Pearson Correlation Calculator

Measure linear association between two equal-length numeric datasets.

Statistics↗

Linear Regression Slope Calculator

Find the ordinary-least-squares slope for Y on X.

Statistics↗

Linear Regression Intercept Calculator

Find the intercept of an ordinary-least-squares Y-on-X line.

Statistics↗

Linear Regression Prediction Calculator

Predict a Y value from a fitted unweighted line and a chosen X value.

Statistics↗

Covariance Calculator

Calculate sample covariance of two paired datasets.

Statistics↗

Mean Absolute Deviation Calculator

Find mean absolute distance from the arithmetic mean.

Statistics↗

Median Absolute Deviation Calculator

Find the median absolute distance from the dataset median.

Statistics↗

Trimmed Mean Calculator

Average a dataset after trimming equal whole-number counts from both tails.

Health & wellbeing↗

BMI Calculator

Calculate adult body mass index from height and weight.

Health & wellbeing↗

BMR Calculator

Estimate adult resting energy expenditure using the simplified Mifflin–St Jeor equation.

Health & wellbeing↗

TDEE Calculator

Estimate adult daily maintenance calorie needs from height, weight, age and a chosen activity multiplier.

Health & wellbeing↗

Calories Burned Calculator

Estimate gross activity energy expenditure using an entered MET value.

Math & percentages↗

What Percent Calculator

Find what percentage one amount represents of another.

Math & percentages↗

Percent of Goal Calculator

Express progress toward a positive numeric target.

Math & percentages↗

Percentage of Percentage Calculator

Find the overall share represented by a percentage within another percentage.

Math & percentages↗

Absolute Value Calculator

Find the non-negative magnitude of a real number.

Math & percentages↗

Remainder Calculator

Find the whole-number remainder after division.

Math & percentages↗

Integer Quotient Calculator

Find how many whole divisor groups fit into a non-negative integer.

Math & percentages↗

Rounding Calculator

Round a number to a chosen number of decimal places.

Math & percentages↗

Round to Nearest Multiple Calculator

Round a measurement or amount to a selected step size.

Math & percentages↗

Floor Function Calculator

Find the integer floor of a real number.

Math & percentages↗

Ceiling Function Calculator

Find the smallest integer at least as large as the input.

Math & percentages↗

Linear Interpolation Calculator

Estimate a value on the straight line between two measured points.

Math & percentages↗

Inverse Linear Interpolation Calculator

Find the input position corresponding to a target value on a straight line.

Math & percentages↗

Direct Proportion Calculator

Scale a directly proportional quantity from one known input-output pair.

Math & percentages↗

Inverse Proportion Calculator

Find a quantity that changes inversely with another quantity.

Math & percentages↗

Arithmetic Sequence Common Difference Calculator

Recover the fixed difference in an arithmetic sequence from two terms.

Math & percentages↗

Geometric Sequence Ratio Calculator

Recover a positive common ratio from two terms of a geometric sequence.

Math & percentages↗

Geometric Mean Growth Rate Calculator

Find a constant two-period growth rate equivalent to two different returns.

Math & percentages↗

Combinations With Repetition Calculator

Count unordered selections when repetition is allowed.

Math & percentages↗

Circular Permutation Calculator

Count distinct circular arrangements of different items.

Math & percentages↗

Permutation With Repetition Calculator

Count ordered codes or sequences when choices can repeat.

Math & percentages↗

Set Subset Count Calculator

Count all subsets of a finite set of distinct elements.

Math & percentages↗

Pair Count Calculator

Count handshakes or unique pairings among distinct participants.

Math & percentages↗

Sum of Integers Calculator

Add all positive integers up to a chosen upper limit.

Math & percentages↗

Sum of Squares Calculator

Add squared integers from one through a selected whole number.

Math & percentages↗

Sum of Cubes Calculator

Add cubed integers from one through a selected whole number.

Math & percentages↗

Fibonacci Number Calculator

Find a term of the Fibonacci sequence using its recurrence.

Math & percentages↗

Collatz Step Count Calculator

Count recurrence steps to reach one for a supported starting integer.

Math & percentages↗

Two by Two Determinant Calculator

Find the determinant of a two-by-two matrix.

Math & percentages↗

Matrix Trace Calculator

Calculate the trace of a three-by-three matrix from its diagonal.

Math & percentages↗

Three by Three Determinant Calculator

Find a three-by-three matrix determinant by cofactor expansion.

Math & percentages↗

Complex Number Magnitude Calculator

Find the magnitude of a complex number from its real and imaginary components.

Math & percentages↗

Complex Number Argument Calculator

Find a complex number’s direction in the complex plane.

Math & percentages↗

Quadratic Vertex X Calculator

Find the horizontal coordinate of a parabola’s vertex.

Math & percentages↗

Quadratic Vertex Y Calculator

Find the vertical coordinate of a quadratic parabola’s vertex.

Math & percentages↗

Polynomial Value Calculator

Evaluate a cubic polynomial at a selected real input.

Math & percentages↗

Polynomial Derivative Calculator

Find the slope of a cubic polynomial at a chosen input.

Math & percentages↗

Definite Polynomial Integral Calculator

Integrate a quadratic polynomial exactly between two bounds.

Math & percentages↗

Linear Equation Intersection X Calculator

Find the x coordinate where two non-parallel straight lines meet.

Math & percentages↗

Logarithmic Growth Time Calculator

Solve the time needed to reach a target under constant compound growth.

Math & percentages↗

Half Life Remaining Amount Calculator

Estimate material remaining after a chosen number of half-lives.

Math & percentages↗

Half Life From Decay Calculator

Recover an exponential half-life from two measured amounts and elapsed time.

Math & percentages↗

Continuous Growth Rate Calculator

Find the continuous exponential rate linking two positive amounts.

Math & percentages↗

Secant Calculator

Find the reciprocal cosine of an angle entered in degrees.

Math & percentages↗

Cosecant Calculator

Find the reciprocal sine of an angle entered in degrees.

Math & percentages↗

Cotangent Calculator

Find the cotangent of an angle entered in degrees.

Math & percentages↗

Hyperbolic Sine Calculator

Evaluate hyperbolic sine for a real argument.

Math & percentages↗

Hyperbolic Cosine Calculator

Evaluate hyperbolic cosine for a real argument.

Math & percentages↗

Hyperbolic Tangent Calculator

Evaluate the hyperbolic tangent of a real argument.

Math & percentages↗

Triangle Third Angle Calculator

Find a triangle’s missing angle from the other two interior angles.

Math & percentages↗

Angle From Rise and Run Calculator

Convert a measured rise-and-run ratio into an inclination angle.

Money & finance↗

Auto Loan Calculator

Estimate vehicle finance payments after a down payment, trade-in credit and financed fees.

Money & finance↗

Refinance Break Even Calculator

Find how long monthly payment savings take to recover refinancing costs.

Money & finance↗

Loan Balance Calculator

Estimate outstanding principal after a chosen number of regular loan payments.

Money & finance↗

Debt Payoff Time Calculator

Estimate whole months to clear a balance with a fixed monthly payment.

Money & finance↗

Credit Card Interest Calculator

Estimate billing-period interest from an average daily credit-card balance.

Money & finance↗

Flat Rate Loan Interest Calculator

Calculate interest under a flat-rate-on-original-principal loan model.

Money & finance↗

Balloon Loan Balance Calculator

Estimate principal remaining after a sequence of partial loan repayments.

Money & finance↗

Equal Principal First Payment Calculator

Find the first payment under a constant-principal-reduction loan schedule.

Money & finance↗

Equal Principal Total Interest Calculator

Calculate interest over an equal-principal repayment schedule.

Money & finance↗

Loan Payment Difference Calculator

Compare monthly payments under two fixed-rate borrowing scenarios.

Money & finance↗

Annuity Due Future Value Calculator

Estimate future value of equal beginning-of-month deposits.

Money & finance↗

Annuity Present Value Calculator

Discount a finite stream of equal end-of-period payments.

Money & finance↗

Annuity Payout Calculator

Find an equal monthly withdrawal that exhausts a balance over a chosen term.

Money & finance↗

Deferred Annuity Present Value Calculator

Discount equal future payments that begin after an additional waiting period.

Money & finance↗

Perpetuity Present Value Calculator

Value an ideal perpetual stream of equal payments.

Money & finance↗

Growing Perpetuity Calculator

Value an ideal infinite payment stream growing at a constant rate.

Money & finance↗

Retirement Fund Target Calculator

Translate a chosen annual retirement-income goal into a fund target under an assumed withdrawal percentage.

Money & finance↗

Retirement Savings Gap Calculator

Estimate the unfunded part of a future retirement target under a chosen growth assumption.

Money & finance↗

Inflation Adjusted Purchasing Power Calculator

Express a future nominal balance in today’s approximate purchasing-power terms.

Money & finance↗

Savings Drawdown Balance Calculator

Estimate a balance after equal withdrawals under a constant-return assumption.

Money & finance↗

Discount Factor Calculator

Find the multiplier that translates a future amount into present value.

Money & finance↗

Holding Period Return Calculator

Measure total simple return including cash received during the holding period.

Money & finance↗

Annualised Simple Return Calculator

Annualise a holding-period return for comparison across different durations.

Money & finance↗

Average Cost Per Share Calculator

Calculate a quantity-weighted average entry price across two purchases.

Money & finance↗

Portfolio Rebalance Amount Calculator

Find the amount needed to move one holding to a target portfolio weight.

Money & finance↗

Price Earnings Ratio Calculator

Compare a share price with entered earnings per share.

Money & finance↗

Earnings Yield Calculator

Express per-share earnings as a percentage of the current share price.

Money & finance↗

Price to Book Ratio Calculator

Compare share market price with entered book value per share.

Money & finance↗

Dividend Payout Ratio Calculator

Measure the share of per-share earnings paid as dividends.

Money & finance↗

Bond Coupon Payment Calculator

Find the periodic coupon amount from bond face value and annual coupon rate.

Money & finance↗

Bond Price Calculator

Discount a fixed bond’s coupons and redemption value at a chosen per-period yield.

Money & finance↗

Investment Fee Drag Calculator

Compare compounded balances with and without an assumed ongoing return reduction.

Money & finance↗

Inflation Linked Payment Calculator

Estimate a future payment that increases at a chosen fixed annual rate.

Money & finance↗

Budget Surplus Calculator

Find money left after entered expenses for a matching income period.

Money & finance↗

Rent to Income Ratio Calculator

Express rent as a share of the monthly take-home income you enter.

Money & finance↗

Income Replacement Ratio Calculator

Compare entered future income with current annual income on a consistent basis.

Money & finance↗

Hourly to Annual Salary Calculator

Translate a regular hourly wage and paid schedule into gross annual earnings.

Money & finance↗

Monthly Salary to Weekly Calculator

Convert recurring monthly gross pay into a weekly equivalent.

Money & finance↗

Pay Rise Calculator

Find gross pay after a chosen percentage salary increase.

Money & finance↗

Real Pay Change Calculator

Adjust a nominal pay change for an entered rate of price inflation.

Money & finance↗

Overtime Total Pay Calculator

Combine regular and overtime earnings into total gross pay for a period.

Business & work↗

Sales Tax Calculator

Calculate a sales-tax amount using a rate you provide.

Business & work↗

Tax Inclusive Price Calculator

Add an entered percentage tax to a pre-tax price.

Business & work↗

VAT Reverse Calculator

Remove an included VAT or GST percentage from a gross amount.

Business & work↗

Tax Included Amount Calculator

Find the tax component within an amount that already includes a percentage tax.

Business & work↗

Price After Markup Calculator

Calculate selling price from a chosen cost-based markup.

Business & work↗

Discount Needed for Target Price Calculator

Find the percentage price reduction needed to reach a chosen sale price.

Business & work↗

Profit Per Unit Calculator

Find the monetary difference between unit revenue and an entered unit cost.

Business & work↗

Sales Volume Growth Calculator

Compare sales quantity growth between two matching periods.

Business & work↗

Break Even Price Calculator

Find the unit selling price that covers entered costs at a planned sales volume.

Business & work↗

Required Sales for Profit Margin Calculator

Work backwards from total costs and a target profit share of revenue.

Business & work↗

Break Even Advertising ROAS Calculator

Estimate the advertising revenue multiple needed to cover ad spend under a contribution-margin model.

Business & work↗

Straight Line Depreciation Calculator

Spread an asset’s depreciable cost evenly over an entered useful life.

Business & work↗

Declining Balance Depreciation Calculator

Calculate one period of declining-balance depreciation at a chosen rate.

Business & work↗

Units of Production Depreciation Calculator

Allocate depreciable asset cost according to production output.

Business & work↗

Double Declining Balance Rate Calculator

Find the conventional annual double-declining depreciation rate.

Business & work↗

Asset Book Value Calculator

Subtract entered accumulated depreciation from an asset’s original cost.

Business & work↗

Return on Assets Calculator

Compare period earnings with average assets employed.

Business & work↗

Return on Equity Calculator

Calculate the ratio of entered equity earnings to average equity.

Business & work↗

Debt to Equity Calculator

Compare an entered measure of business debt with positive equity.

Business & work↗

Interest Coverage Calculator

Measure accounting earnings cover of entered interest expense.

Business & work↗

Debt Service Coverage Calculator

Compare entered cash available with scheduled principal and interest payments.

Business & work↗

Asset Turnover Calculator

Express sales generated per unit of average assets.

Business & work↗

Receivables Turnover Calculator

Measure how often an average receivable balance is collected relative to credit sales.

Business & work↗

Days Sales Outstanding Calculator

Convert receivable balance and matching credit sales into approximate collection days.

Business & work↗

Days Payable Outstanding Calculator

Estimate supplier-payment days from payables and an entered cost base.

Business & work↗

Cash Conversion Cycle Calculator

Combine inventory, collection and payment days into a cash operating cycle estimate.

Business & work↗

Customer Lifetime Value Calculator

Estimate customer lifetime gross profit from order behaviour and an entered duration.

Business & work↗

LTV to CAC Ratio Calculator

Compare an entered lifetime customer value with acquisition cost.

Business & work↗

CAC Payback Months Calculator

Estimate months of customer gross profit needed to recover acquisition spending.

Business & work↗

Click to Open Rate Calculator

Measure email clicks relative to unique opens rather than delivered emails.

Business & work↗

Email Open Rate Calculator

Find unique recorded opens as a share of delivered campaign emails.

Business & work↗

Click Through Rate Calculator

Calculate advertising clicks as a percentage of recorded impressions.

Business & work↗

Revenue Per Visitor Calculator

Compare attributed revenue with the number of visitors in the same period.

Business & work↗

Cart Abandonment Rate Calculator

Find the share of started shopping carts that did not become completed purchases.

Business & work↗

Net Promoter Score Calculator

Calculate a net promoter score from grouped survey counts.

Business & work↗

Customer Satisfaction Score Calculator

Express satisfied survey responses as a percentage of valid responses.

Business & work↗

Net Revenue Retention Calculator

Measure recurring-revenue retention including expansion in an existing customer cohort.

Business & work↗

Gross Revenue Retention Calculator

Measure recurring-revenue retention before expansion in the starting customer cohort.

Business & work↗

Overall Equipment Effectiveness Calculator

Combine availability, performance and quality into OEE.

Business & work↗

Takt Time Calculator

Find the production pace needed to match an entered customer demand.

Business & work↗

Cycle Time Calculator

Measure average time per completed production unit.

Business & work↗

Production Rate Calculator

Express measured output as units per operating hour.

Business & work↗

Scrap Rate Calculator

Find scrapped units as a share of total process input.

Business & work↗

First Pass Yield Calculator

Measure the share of process units accepted without rework.

Business & work↗

Reorder Point Calculator

Estimate the stock level at which replenishment should be triggered under entered assumptions.

Business & work↗

Economic Order Quantity Calculator

Estimate the order size balancing simple ordering and holding costs.

Business & work↗

Annual Inventory Holding Cost Calculator

Estimate the annual cost of carrying a chosen average stock balance.

Construction & DIY↗

Drywall Sheet Calculator

Estimate whole plasterboard or drywall sheets for a net measured area.

Construction & DIY↗

Drywall Screw Calculator

Plan screw quantities from a manufacturer-appropriate fixing rate.

Construction & DIY↗

Roof Area Calculator

Estimate uniformly pitched roof surface area from a horizontal footprint.

Construction & DIY↗

Roofing Squares Calculator

Express a roof covering area in US roofing squares with an entered waste allowance.

Construction & DIY↗

Roof Shingle Bundle Calculator

Estimate whole roof-shingle bundles from product-specific coverage.

Construction & DIY↗

Roof Underlay Roll Calculator

Plan roofing underlay rolls using net installed coverage per roll.

Construction & DIY↗

Rafter Length Calculator

Estimate common-rafter slope length from a roof span, rise and overhang.

Construction & DIY↗

Roof Pitch Ratio Calculator

Express a roof slope in the familiar rise-in-twelve convention.

Construction & DIY↗

Roof Ridge Cap Calculator

Estimate ridge-cap pieces using installed linear coverage.

Construction & DIY↗

Siding Quantity Calculator

Estimate whole siding or cladding packs for measured exterior wall area.

Construction & DIY↗

Deck Board Calculator

Estimate the number of parallel boards across a rectangular deck width.

Construction & DIY↗

Deck Joist Quantity Calculator

Count joist positions for a simple open rectangular layout at entered maximum centres.

Construction & DIY↗

Wall Stud Quantity Calculator

Estimate positions of regularly spaced studs plus an explicit extra-stud allowance.

Construction & DIY↗

Plywood Sheet Calculator

Estimate sheet quantities for plywood or similar sheet-material coverage.

Construction & DIY↗

Timber Volume Calculator

Find total solid timber volume from actual board dimensions and quantity.

Construction & DIY↗

Lumber Weight Calculator

Estimate timber mass from measured solid volume and a chosen density.

Construction & DIY↗

Concrete Column Calculator

Estimate concrete volume for repeated solid round columns.

Construction & DIY↗

Concrete Footing Calculator

Estimate wet concrete quantity for a uniform rectangular strip footing.

Construction & DIY↗

Concrete Bag Calculator

Convert wet concrete demand into whole bags of a selected premix.

Construction & DIY↗

Post Hole Concrete Calculator

Estimate concrete around cylindrical posts in round holes.

Construction & DIY↗

Concrete Stair Volume Calculator

Calculate solid concrete volume for a simple repeated step profile.

Construction & DIY↗

Concrete Block Calculator

Estimate concrete masonry units from wall area and block-plus-joint face dimensions.

Construction & DIY↗

Mortar Volume Calculator

Estimate geometric mortar-joint volume from gross masonry and unit envelope volumes.

Construction & DIY↗

Tile Grout Quantity Calculator

Estimate tile-joint grout mass from dimensions and a supplied mixed density.

Construction & DIY↗

Tile Adhesive Quantity Calculator

Convert an adhesive consumption rate into whole bags for a tiling area.

Construction & DIY↗

Wallpaper Pattern Drop Calculator

Round wallpaper cut length up to a whole pattern repeat.

Construction & DIY↗

Paint Cost Calculator

Estimate paint and additional supply cost after working out the paint quantity.

Construction & DIY↗

Skirting Board Length Calculator

Estimate skirting or baseboard length after deducting doorway openings.

Construction & DIY↗

Carpet Cost Calculator

Estimate carpet spending using roll width, purchased length and fitting costs.

Construction & DIY↗

Insulation Pack Calculator

Estimate whole insulation packs using the selected product’s installed coverage.

Construction & DIY↗

Asphalt Tonnage Calculator

Estimate compacted asphalt mass from area, thickness and mix density.

Construction & DIY↗

Excavation Volume Calculator

Estimate excavated in-place volume for a rectangular dig.

Construction & DIY↗

Soil Swell Volume Calculator

Estimate loose spoil volume after a chosen expansion allowance.

Construction & DIY↗

Skip Load Count Calculator

Estimate waste-container loads from a loose-volume quantity and usable capacity.

Construction & DIY↗

Fence Rail Length Calculator

Estimate total horizontal rail length for a simple fence run.

Construction & DIY↗

Fence Picket Calculator

Estimate vertical fence pickets for a measured clear run and selected spacing.

Construction & DIY↗

Baluster Gap Calculator

Distribute equal gaps around and between a chosen number of balusters.

Construction & DIY↗

Stair Tread Run Calculator

Find the horizontal run of a straight stair from riser count and tread going.

Construction & DIY↗

Stair Stringer Length Calculator

Estimate the sloping length of a straight stair stringer.

Construction & DIY↗

Miter Angle Calculator

Find the equal miter-saw angle for a regular polygon frame.

Construction & DIY↗

Construction Contingency Calculator

Add a chosen contingency percentage to a project cost estimate.

Construction & DIY↗

Material Delivery Cost Per Unit Calculator

Allocate purchase and delivery spending over a material quantity.

Geometry↗

Square Area Calculator

Find the area enclosed by a square from one side measurement.

Geometry↗

Square Diagonal Calculator

Find the corner-to-corner distance of a square.

Geometry↗

Square Side From Area Calculator

Recover square side length from its enclosed area.

Geometry↗

Rhombus Perimeter Calculator

Find the perimeter of a rhombus from one side.

Geometry↗

Regular Polygon Perimeter Calculator

Find the outline length of a regular polygon.

Geometry↗

Polygon Diagonal Count Calculator

Count all vertex-to-vertex diagonals in a polygon.

Geometry↗

Polygon Interior Angle Sum Calculator

Find the sum of all interior angles in a simple polygon.

Geometry↗

Regular Polygon Exterior Angle Calculator

Find the equal exterior turning angle of a regular polygon.

Geometry↗

Regular Polygon Apothem Calculator

Find the inradius of a regular polygon from side length and side count.

Geometry↗

Triangle Area From Two Sides Calculator

Find a triangle’s area from two sides and their included angle.

Geometry↗

Triangle Altitude Calculator

Recover a triangle’s perpendicular height from area and base.

Geometry↗

Triangle Inradius Calculator

Find the radius of a triangle’s inscribed circle from its side lengths.

Geometry↗

Triangle Circumradius Calculator

Find the radius of the circle through all three triangle vertices.

Geometry↗

Triangle Median Calculator

Find a triangle median length from its three side lengths.

Geometry↗

Circle Radius From Area Calculator

Recover a circle’s radius from its enclosed area.

Geometry↗

Circle Radius From Circumference Calculator

Recover a circle’s radius from its circumference.

Geometry↗

Ellipse Perimeter Calculator

Estimate the circumference of an ellipse from its semi-axes.

Geometry↗

Circular Sector Perimeter Calculator

Find the boundary length of a sector bounded by an arc and two radii.

Geometry↗

Cube Volume Calculator

Find the volume enclosed by a cube from one edge.

Geometry↗

Cube Space Diagonal Calculator

Find the longest corner-to-corner distance within a cube.

Geometry↗

Hemisphere Volume Calculator

Find the volume of a hemisphere.

Geometry↗

Hemisphere Surface Area Calculator

Find the combined curved and base surface area of a hemisphere.

Geometry↗

Spherical Cap Volume Calculator

Find the volume cut from a sphere by a plane at a chosen cap height.

Geometry↗

Spherical Cap Surface Area Calculator

Find the curved surface area of a spherical cap.

Geometry↗

Triangular Prism Volume Calculator

Find the volume of a uniform triangular prism.

Geometry↗

Torus Surface Area Calculator

Find the outside surface area of a ring-shaped torus.

Geometry↗

Capsule Volume Calculator

Calculate the volume of a cylinder capped by two hemispheres.

Geometry↗

Capsule Surface Area Calculator

Find the external area of a cylinder with hemispherical ends.

Geometry↗

Hollow Cylinder Material Volume Calculator

Find material volume of a uniform hollow cylindrical tube.

Geometry↗

Horizontal Cylinder Liquid Volume Calculator

Find partial fill volume from liquid depth in a horizontal cylindrical tank.

Geometry↗

Frustum Slant Height Calculator

Find the sloping side length of a truncated cone.

Geometry↗

Pyramid Lateral Area Calculator

Find side-face area of a regular pyramid.

Geometry↗

Rectangular Pyramid Surface Area Calculator

Find the base and triangular-face areas of a centred rectangular pyramid.

Geometry↗

Vector Magnitude Calculator

Find the length of a three-dimensional vector.

Geometry↗

Angle Between Vectors Calculator

Find the unsigned angle between two nonzero 3D vectors.

Geometry↗

Point to Line Distance Calculator

Find perpendicular distance from a point to a straight line.

Geometry↗

Point to Plane Distance Calculator

Find perpendicular distance from a 3D point to a plane.

Physics↗

Average Velocity Calculator

Find average velocity along a chosen coordinate direction.

Physics↗

Velocity From Distance and Acceleration Calculator

Use the time-independent kinematic relationship to find a final speed magnitude.

Physics↗

Projectile Flight Time Calculator

Find ideal total flight time for a projectile returning to launch height.

Physics↗

Horizontal Projectile Time Calculator

Find time to fall for a projectile launched horizontally from a height.

Physics↗

Horizontal Projectile Range Calculator

Find horizontal travel before an ideal horizontally launched object reaches the ground.

Physics↗

Relative Speed Calculator

Find relative speed between two objects moving along the same line.

Physics↗

Catch Up Time Calculator

Find when a faster pursuer reaches a slower object ahead.

Physics↗

Meeting Time Calculator

Find time for two approaching objects to meet.

Physics↗

Rotational Period Calculator

Find time per full rotation from a rotational speed.

Physics↗

Angular Acceleration Calculator

Find angular acceleration from a change in angular velocity.

Physics↗

Weight Force Calculator

Calculate gravitational weight from mass and a selected gravitational acceleration.

Physics↗

Normal Force on Incline Calculator

Find the perpendicular contact force for an object resting on an ideal incline.

Physics↗

Incline Gravity Component Calculator

Resolve gravitational force parallel to an inclined surface.

Physics↗

Static Friction Limit Calculator

Estimate the maximum static friction magnitude before sliding under a simple contact model.

Physics↗

Impulse From Momentum Calculator

Find impulse from a change in linear momentum.

Physics↗

Collision Common Velocity Calculator

Find shared velocity after two masses stick together in an ideal collision.

Physics↗

Coefficient of Restitution Calculator

Compare relative separation and approach speeds in a one-dimensional collision.

Physics↗

Rotational Kinetic Energy Calculator

Find kinetic energy stored in rigid-body rotation.

Physics↗

Solid Disc Moment of Inertia Calculator

Find the central-axis moment of inertia of a uniform solid disc.

Physics↗

Thin Ring Moment of Inertia Calculator

Find the moment of inertia of an ideal thin ring.

Physics↗

Solid Sphere Moment of Inertia Calculator

Find rotational inertia of a uniform solid sphere about its centre.

Physics↗

Parallel Axis Theorem Calculator

Translate moment of inertia to a parallel offset axis.

Physics↗

Angular Momentum Calculator

Calculate scalar angular momentum for a rigid rotor.

Physics↗

Rotational Power Calculator

Find shaft mechanical power from torque and angular velocity.

Physics↗

Hydraulic Force Calculator

Find ideal actuator force from differential pressure and effective piston area.

Physics↗

Hydraulic Press Output Calculator

Estimate force multiplication in an ideal hydraulic press.

Physics↗

Pipe Flow Velocity Calculator

Convert pipe volume flow into average velocity.

Physics↗

Continuity Equation Calculator

Find flow speed after a cross-sectional area change under continuity.

Physics↗

Dynamic Pressure Calculator

Calculate dynamic pressure from fluid density and speed.

Physics↗

Bernoulli Pressure Difference Calculator

Estimate static-pressure change due to a speed change in ideal horizontal flow.

Physics↗

Darcy Weisbach Head Loss Calculator

Estimate straight-pipe friction head loss from an entered Darcy factor.

Physics↗

Minor Loss Head Calculator

Estimate fitting or local head loss from a supplied loss coefficient.

Physics↗

Hydraulic Pump Power Calculator

Estimate input power for a fluid flow and head scenario.

Physics↗

Torricelli Efflux Speed Calculator

Find ideal liquid outlet speed under a chosen hydrostatic head.

Physics↗

Capillary Rise Calculator

Estimate capillary rise or depression in a small circular tube.

Physics↗

Thermal Resistance Flat Layer Calculator

Find thermal resistance of an ideal uniform planar layer.

Physics↗

Heat Pump COP Calculator

Compare delivered heating energy with electrical input for a measured interval.

Physics↗

Carnot Efficiency Calculator

Find the Carnot thermal-efficiency limit from absolute reservoir temperatures.

Physics↗

Ideal Gas Isothermal Work Calculator

Estimate reversible work during an isothermal ideal-gas volume change.

Physics↗

Ideal Gas Internal Energy Change Calculator

Calculate ideal-gas internal-energy change using an entered heat capacity.

Physics↗

First Law Heat Calculator

Apply the first law of thermodynamics with an explicit work-sign convention.

Physics↗

Thermal Energy Mixing Temperature Calculator

Estimate equilibrium temperature after mixing two quantities of the same substance.

Physics↗

Stefan Boltzmann Radiation Calculator

Estimate net radiative heat transfer with a stated emissivity.

Physics↗

Wien Peak Wavelength Calculator

Find the peak wavelength of an ideal blackbody spectrum.

Physics↗

Snells Law Calculator

Find the refracted ray angle at a boundary between optical media.

Physics↗

Critical Angle Calculator

Find the incidence angle at which ideal total internal reflection begins.

Physics↗

Thin Lens Image Distance Calculator

Find ideal image distance for a thin lens and a real object.

Physics↗

Lens Magnification Calculator

Find signed lateral magnification from object and image distances.

Physics↗

Lens Power Calculator

Convert a lens focal length in metres into optical power.

Physics↗

Refractive Index From Speed Calculator

Find optical refractive index from an entered light phase speed.

Physics↗

Photon Energy Calculator

Calculate the energy of a photon from its vacuum wavelength.

Physics↗

Photon Frequency Calculator

Convert a vacuum light wavelength into electromagnetic frequency.

Physics↗

De Broglie Wavelength Calculator

Find the matter-wave wavelength corresponding to a momentum magnitude.

Physics↗

Young Double Slit Fringe Calculator

Estimate ideal double-slit fringe spacing on a distant screen.

Electrical↗

Wire Resistance Calculator

Estimate conductor resistance from material resistivity, length and area.

Electrical↗

Resistivity Calculator

Recover resistivity from a uniform sample’s resistance and dimensions.

Electrical↗

Resistance Temperature Calculator

Estimate resistance change from a supplied linear temperature coefficient.

Electrical↗

Current Density Calculator

Find average electrical current per conductor cross-sectional area.

Electrical↗

Electric Charge Calculator

Find charge transferred during a current flow interval.

Electrical↗

Current From Charge Calculator

Calculate average current from total transferred charge.

Electrical↗

Capacitor Charge Calculator

Find electric charge stored on an ideal capacitor.

Electrical↗

Capacitor Charging Voltage Calculator

Estimate voltage during ideal first-order RC charging.

Electrical↗

Capacitor Discharge Voltage Calculator

Estimate capacitor voltage after an ideal RC discharge interval.

Electrical↗

Inductor Energy Calculator

Find magnetic energy stored in an ideal inductor.

Electrical↗

Inductor Voltage Calculator

Find ideal inductor voltage from the rate of current change.

Electrical↗

Series Inductance Calculator

Add two uncoupled inductors connected in series.

Electrical↗

Parallel Inductance Calculator

Find equivalent inductance for two uncoupled parallel inductors.

Electrical↗

Parallel Plate Capacitance Calculator

Estimate ideal capacitance from plate geometry and dielectric permittivity.

Electrical↗

Battery Series Voltage Calculator

Find the nominal voltage sum for identical battery units in series.

Electrical↗

Battery Parallel Capacity Calculator

Find the nominal amp-hour sum of an ideal compatible parallel battery bank.

Electrical↗

Battery C Rate Calculator

Express charge or discharge current relative to battery capacity.

Electrical↗

Inverter Input Current Calculator

Estimate inverter DC current from output load and assumed efficiency.

Electrical↗

DC Converter Efficiency Calculator

Compare measured DC converter output and input power.

Electrical↗

Resistor Colour Value Calculator

Decode a conventional resistor’s two digits and multiplier into resistance.

Electrical↗

Single Phase AC Current Calculator

Find single-phase RMS current from real power, voltage and power factor.

Electrical↗

Three Phase Current Calculator

Find line current for a balanced three-phase real-power load.

Electrical↗

Reactive Power Calculator

Find reactive-power magnitude from compatible apparent and real power.

Electrical↗

Power Factor Angle Calculator

Convert a sinusoidal displacement power factor into phase-angle magnitude.

Electrical↗

Power Factor Correction Calculator

Estimate reactive compensation needed to raise an entered displacement power factor.

Electrical↗

Series RLC Impedance Calculator

Find impedance magnitude for a series RLC circuit from component reactances.

Electrical↗

Series RLC Phase Angle Calculator

Find the ideal voltage-current phase angle of a series RLC impedance.

Electrical↗

RC Low Pass Cutoff Calculator

Find the minus-three-decibel cutoff of an ideal RC low-pass filter.

Electrical↗

RL Filter Cutoff Calculator

Find the characteristic cutoff frequency of a simple RL filter.

Electrical↗

Decibel Power Ratio Calculator

Express a power ratio as a decibel difference.

Electrical↗

Decibel Voltage Ratio Calculator

Express a voltage amplitude ratio as a decibel difference.

Electrical↗

Decibels to Power Ratio Calculator

Recover a linear power ratio from a decibel difference.

Electrical↗

Decibels to Voltage Ratio Calculator

Recover a voltage amplitude ratio from a decibel difference.

Electrical↗

Motor Synchronous Speed Calculator

Find synchronous rotating-field speed from frequency and pole count.

Electrical↗

Induction Motor Slip Calculator

Compare rotor speed with a synchronous reference speed.

Electrical↗

Motor Shaft Torque Calculator

Find shaft torque from mechanical power and rotational speed.

Electrical↗

Transformer Secondary Current Calculator

Find ideal transformer secondary current from current and turns ratio.

Engineering & manufacturing↗

Steel Plate Weight Calculator

Estimate solid plate mass from dimensions and a supplied steel density.

Engineering & manufacturing↗

Round Bar Weight Calculator

Estimate mass of a solid circular bar.

Engineering & manufacturing↗

Square Bar Weight Calculator

Estimate mass of a uniform solid square bar.

Engineering & manufacturing↗

Rectangular Tube Weight Calculator

Estimate material mass of a rectangular hollow tube.

Engineering & manufacturing↗

Round Tube Weight Calculator

Estimate weight of a circular hollow tube from outside diameter and wall thickness.

Engineering & manufacturing↗

Metal Ring Weight Calculator

Estimate metal washer or ring mass from annular geometry.

Engineering & manufacturing↗

Angle Bar Weight Calculator

Estimate mass of an ideal equal- or unequal-leg angle section.

Engineering & manufacturing↗

Sheet Material Cost Calculator

Estimate raw material cost from sheet geometry and a mass-based price.

Engineering & manufacturing↗

Mass From Cross Section Calculator

Estimate a uniform section’s mass when its cross-sectional area is known.

Engineering & manufacturing↗

Cut Stock Piece Count Calculator

Estimate full pieces available from one stock length including a repeated kerf allowance.

Engineering & manufacturing↗

Tensile Stress Calculator

Find average tensile stress in a loaded net section.

Engineering & manufacturing↗

Engineering Strain Calculator

Calculate dimensionless engineering strain from elongation and original length.

Engineering & manufacturing↗

Youngs Modulus Calculator

Estimate Young’s modulus from an elastic stress-strain pair.

Engineering & manufacturing↗

Axial Elongation Calculator

Estimate elastic length change of a uniform axially loaded bar.

Engineering & manufacturing↗

Shear Stress Calculator

Find average shear stress over an entered area.

Engineering & manufacturing↗

Bearing Stress Calculator

Estimate nominal pin or bolt bearing stress on a plate.

Engineering & manufacturing↗

Poissons Ratio Calculator

Calculate Poisson’s ratio from transverse and longitudinal strain.

Engineering & manufacturing↗

Shear Modulus From Youngs Modulus Calculator

Relate shear modulus to Young’s modulus and Poisson’s ratio.

Engineering & manufacturing↗

Thermal Stress Restrained Bar Calculator

Estimate ideal axial stress when a bar cannot thermally expand.

Engineering & manufacturing↗

Factor of Safety Ratio Calculator

Compare an entered strength value with a compatible working-stress estimate.

Engineering & manufacturing↗

Gear Ratio Calculator

Find the tooth-count ratio of a simple gear pair.

Engineering & manufacturing↗

Gear Output Speed Calculator

Find output rotational speed from an input speed and two gear tooth counts.

Engineering & manufacturing↗

Gear Pitch Diameter Calculator

Find nominal pitch diameter from gear module and tooth count.

Engineering & manufacturing↗

Gear Centre Distance Calculator

Estimate standard centre distance for two external gears of the same module.

Engineering & manufacturing↗

Belt Drive Output Speed Calculator

Estimate speed ratio for a two-pulley belt drive.

Engineering & manufacturing↗

Belt Linear Speed Calculator

Find belt linear speed from pulley pitch diameter and rotational speed.

Engineering & manufacturing↗

Open Belt Length Calculator

Estimate the pitch length of an open two-pulley belt.

Engineering & manufacturing↗

Lead Screw Linear Speed Calculator

Translate screw rotation into ideal axial travel rate.

Engineering & manufacturing↗

Spindle Speed Calculator

Convert a selected metric cutting speed and diameter into spindle speed.

Engineering & manufacturing↗

Cutting Speed Calculator

Find surface cutting speed from tool diameter and rotational speed.

Engineering & manufacturing↗

Milling Feed Rate Calculator

Calculate nominal milling table feed from tooth count, chip load and spindle speed.

Engineering & manufacturing↗

Feed Per Tooth Calculator

Recover nominal milling chip load from table feed and rotational speed.

Engineering & manufacturing↗

Turning Feed Rate Calculator

Convert a turning feed per revolution into linear travel rate.

Engineering & manufacturing↗

Milling Removal Rate Calculator

Estimate nominal metal removal rate for a milling pass.

Engineering & manufacturing↗

Machining Time Calculator

Estimate feed-motion time for a machining pass.

Engineering & manufacturing↗

Tap Drill Estimate Calculator

Estimate a cutting-tap pilot diameter from a metric diameter and pitch.

Engineering & manufacturing↗

Drill Point Length Calculator

Find axial point length for an ideal drill tip.

Engineering & manufacturing↗

Turning Diameter Reduction Time Calculator

Estimate repeated turning-pass feed time from travel, feed and speed.

Engineering & manufacturing↗

Drilling Material Removal Rate Calculator

Find nominal drilling removal rate from hole diameter and feed.

Engineering & manufacturing↗

Machining Cost Calculator

Combine estimated machining time with an hourly rate and extra costs.

Garden & agriculture↗

Plant Spacing Calculator

Estimate planting density from row and in-row spacing.

Garden & agriculture↗

Plant Row Count Calculator

Count evenly spaced planting rows across a defined clear width.

Garden & agriculture↗

Plants Per Row Calculator

Count plant positions along a usable row with selected spacing.

Garden & agriculture↗

Triangular Plant Spacing Calculator

Estimate plant density in a staggered equilateral-triangle arrangement.

Garden & agriculture↗

Seed Quantity Calculator

Calculate total seed mass from an entered area-based sowing rate.

Garden & agriculture↗

Grass Seed Bag Calculator

Convert a grass seed coverage specification into whole bag quantities.

Garden & agriculture↗

Seed Germination Adjustment Calculator

Adjust seed count for a chosen expected germination percentage.

Garden & agriculture↗

Seed Survival Adjustment Calculator

Plan seed count when both germination and later survival losses are entered.

Garden & agriculture↗

Raised Bed Soil Calculator

Estimate fill volume for a rectangular raised garden bed.

Garden & agriculture↗

Round Planter Soil Calculator

Estimate soil volume for a straight-sided round planter.

Garden & agriculture↗

Tapered Planter Soil Calculator

Estimate soil fill volume for a tapered round plant pot.

Garden & agriculture↗

Potting Mix Blend Calculator

Allocate one ingredient of a volume-based potting mix recipe.

Garden & agriculture↗

Compost Spread Volume Calculator

Estimate compost volume for an even layer over a measured area.

Garden & agriculture↗

Growing Medium Bag Calculator

Convert a potting-medium volume requirement into whole bags.

Garden & agriculture↗

Irrigation Volume Calculator

Translate a selected irrigation depth into water volume.

Garden & agriculture↗

Irrigation Runtime Calculator

Find watering duration from a water-volume target and flow rate.

Garden & agriculture↗

Sprinkler Precipitation Rate Calculator

Convert sprinkler flow and coverage area into an average application rate.

Garden & agriculture↗

Drip Irrigation Total Flow Calculator

Estimate total nominal flow of equal drip emitters.

Garden & agriculture↗

Drip Water Per Plant Calculator

Find water delivered per plant during a drip-irrigation interval.

Garden & agriculture↗

Irrigation Gross Depth Calculator

Account for an assumed application efficiency in a water-depth budget.

Garden & agriculture↗

Rainfall Irrigation Offset Calculator

Subtract entered effective rainfall from a chosen irrigation-depth target.

Garden & agriculture↗

Rain Gauge Catch Depth Calculator

Convert collected water volume and opening area into rainfall depth.

Garden & agriculture↗

Irrigation Energy Cost Calculator

Estimate electricity spending for an irrigation pump run.

Garden & agriculture↗

Crop Yield Per Area Calculator

Express measured harvest quantity per unit area.

Garden & agriculture↗

Crop Revenue Calculator

Estimate gross harvest revenue from saleable weight and an entered price.

Garden & agriculture↗

Harvest Loss Percentage Calculator

Compare saleable harvest with an entered pre-loss quantity.

Garden & agriculture↗

Fertilizer Product Quantity Calculator

Convert a supplied nutrient requirement into product mass using the labelled nutrient percentage.

Garden & agriculture↗

Fertilizer Nutrient Content Calculator

Find mass of one labelled nutrient component in a fertilizer amount.

Garden & agriculture↗

Seeding Rate Per Hectare Calculator

Calculate an actual mass-based sowing rate from seed use and land area.

Garden & agriculture↗

Thousand Seed Weight Count Calculator

Estimate seed count from sample mass and an entered thousand-seed weight.

Chemistry↗

Molar Mass From Sample Calculator

Recover molar mass from a known sample mass and amount of substance.

Chemistry↗

Solvent Mass From Molality Calculator

Find solvent mass for an entered molality and solute amount.

Chemistry↗

Molarity From Mass Concentration Calculator

Convert a mass concentration into molar concentration.

Chemistry↗

Mass From Weight Percent Solution Calculator

Find solute mass in a mixture specified by mass percentage.

Chemistry↗

Solvent Mass in Solution Calculator

Separate solvent mass from a two-component solution mass and solute percentage.

Chemistry↗

Dilution Factor Calculator

Express a concentration reduction as a dilution multiple.

Chemistry↗

Serial Dilution Concentration Calculator

Estimate concentration after equal serial dilution stages.

Chemistry↗

Solvent Addition for Dilution Calculator

Estimate solvent addition needed to dilute a fixed stock-solution volume.

Chemistry↗

Volume Percent Calculator

Express a component’s entered volume as a percentage of final mixture volume.

Chemistry↗

Mass Volume Percent Calculator

Find the grams-per-100-millilitres concentration of a solution.

Chemistry↗

Ideal Strong Acid pH Calculator

Estimate concentration-based pH under an explicitly ideal strong-acid model.

Chemistry↗

Ideal Strong Base pH Calculator

Estimate an ideal strong-base pH under a stated room-temperature approximation.

Chemistry↗

Henderson Hasselbalch Calculator

Estimate buffer pH from an entered pKa and conjugate-base-to-acid ratio.

Chemistry↗

Beer Lambert Absorbance Calculator

Find ideal optical absorbance from concentration and optical path length.

Chemistry↗

Concentration From Absorbance Calculator

Recover concentration under a linear absorbance model.

Chemistry↗

Transmittance to Absorbance Calculator

Convert a transmitted-light percentage into base-ten absorbance.

Chemistry↗

Absorbance to Transmittance Calculator

Express absorbance as a transmitted fraction of incident light.

Chemistry↗

Ideal Gas Volume Calculator

Find ideal gas volume from amount, pressure and temperature.

Chemistry↗

Ideal Gas Temperature Calculator

Recover ideal gas absolute temperature from pressure, volume and amount.

Chemistry↗

Daltons Partial Pressure Calculator

Find a gas component’s partial pressure from its mole fraction.

Chemistry↗

Gas Mole Fraction From Pressure Calculator

Recover ideal gas mole fraction from a component pressure and total pressure.

Chemistry↗

Ideal Gas Molar Volume Calculator

Find molar volume for an ideal gas at selected conditions.

Chemistry↗

First Order Reaction Remaining Calculator

Estimate reactant concentration after a first-order reaction interval.

Chemistry↗

First Order Reaction Half Life Calculator

Find half-life from a first-order reaction rate constant.

Chemistry↗

Reaction Conversion Calculator

Find the consumed fraction of an initially supplied reactant.

Computing & digital↗

Bandwidth Delay Product Calculator

Estimate data in flight needed to fill a link across an entered round-trip delay.

Computing & digital↗

TCP Window Throughput Calculator

Estimate a simple transport window and RTT throughput ceiling.

Computing & digital↗

Network Utilisation Calculator

Compare measured traffic with an entered nominal link capacity.

Computing & digital↗

Download Speed Required Calculator

Find the sustained payload speed required to download a file within a target time.

Computing & digital↗

Upload Time Calculator

Estimate the time required to upload a decimal-megabyte file.

Computing & digital↗

IPv4 Address Count Calculator

Find the full address count represented by an IPv4 prefix.

Computing & digital↗

IPv4 Conventional Usable Hosts Calculator

Count traditional usable host addresses after reserving network and broadcast addresses.

Computing & digital↗

Equal Subnet Count Calculator

Count equal subnets created by extending a network prefix.

Computing & digital↗

Signal to Noise Ratio Calculator

Compare signal power with noise power as a decibel ratio.

Computing & digital↗

Shannon Channel Capacity Calculator

Estimate the Shannon capacity bound for a bandwidth and linear SNR assumption.

Computing & digital↗

Streaming Data Usage Calculator

Estimate video or audio streaming data from an average bitrate and viewing time.

Computing & digital↗

Render Farm Time Calculator

Estimate ideal parallel rendering time for a fixed frame workload.

Computing & digital↗

Animation Duration Calculator

Translate a frame count into constant-rate animation duration.

Computing & digital↗

Image Scaling Percentage Calculator

Find the resize multiplier expressed as a percentage of original width.

Computing & digital↗

Cloud Storage Cost Calculator

Estimate simple flat-rate cloud storage charges from average usage.

Computing & digital↗

Cloud Compute Cost Calculator

Estimate constant-rate compute-instance spending.

Computing & digital↗

Data Growth Storage Calculator

Project data volume under a chosen recurring percentage-growth scenario.

Computing & digital↗

Backup Transfer Window Calculator

Estimate transfer time for a decimal-gigabyte backup over a sustained payload link.

Computing & digital↗

Password Search Space Bits Calculator

Measure the theoretical information content of a uniform random character model.

Computing & digital↗

Average Brute Force Time Calculator

Translate an ideal search-space size and assumed test rate into an average search time.

Math & percentages↗

Quadratic Formula Calculator

Find both real or complex roots of a quadratic equation.

Math & percentages↗

Two Equation Linear System Calculator

Solve two simultaneous linear equations in two unknowns.

Math & percentages↗

Two by Two Matrix Inverse Calculator

Find the inverse of a non-singular two-by-two matrix.

Geometry↗

Vector Cross Product Calculator

Find the three components of the cross product of two 3D vectors.

Geometry↗

Midpoint Calculator

Find the midpoint coordinates between two plane points.

Date & time↗

Leap Year Calculator

Check whether a Gregorian calendar year has 366 days.

Date & time↗

Hours Minutes to Decimal Calculator

Convert a duration in whole hours and minutes into decimal hours.

Date & time↗

Decimal Hours to Hours Minutes Calculator

Express a non-negative decimal-hour duration as whole hours and rounded minutes.

Date & time↗

Unix Timestamp to UTC Calculator

Convert Unix seconds to a UTC date-time string.

Date & time↗

Date to Unix Timestamp Calculator

Convert a civil date at UTC midnight into Unix seconds.

Money & finance↗

NPV Calculator

Find net present value of evenly spaced cash flows, including an initial time-zero amount.

Money & finance↗

IRR Calculator

Estimate one periodic internal rate of return for a conventional cash-flow sequence.

Money & finance↗

MIRR Calculator

Estimate modified internal rate of return with separate finance and reinvestment rates.

Money & finance↗

Loan Rate From Payment Calculator

Estimate a non-negative nominal annual loan rate from a level monthly payment.

Money & finance↗

Amortization Schedule Calculator

Calculate a level monthly payment and a month-by-month principal-and-interest schedule.

Food & cooking↗

Cups to Grams Calculator

Convert cup volume to ingredient mass using an explicit cup convention and density.

Food & cooking↗

Grams to Cups Calculator

Translate an ingredient mass into cups using a chosen bulk density and cup volume.

Food & cooking↗

Food Energy Calculator

Estimate food energy from entered macronutrient amounts.

Food & cooking↗

Calories Per Serving Calculator

Divide total recipe calories across equal servings.

Food & cooking↗

Protein Per Serving Calculator

Allocate an entered recipe protein total to equal portions.

Food & cooking↗

Cooked Food Yield Calculator

Estimate cooked mass using an explicitly entered yield factor.

Food & cooking↗

Recipe Ingredient Cost Calculator

Allocate a package’s purchase cost to the amount used in a recipe.

Food & cooking↗

Coffee Cost Per Cup Calculator

Estimate coffee-bean cost for one drink from bag price and dose.

Food & cooking↗

Coffee Bag Supply Calculator

Estimate how long a coffee bag lasts at a selected daily drink rate.

Food & cooking↗

Food Waste Cost Calculator

Put a monetary value on entered edible food waste.

Food & cooking↗

Pizza Price Comparison Calculator

Compare two round pizzas by price per unit of area rather than diameter alone.

Food & cooking↗

Round to Rectangular Pan Recipe Calculator

Scale a round-pan recipe to a rectangular pan by area.

Fitness & sport↗

One Rep Max Calculator

Estimate one-repetition maximum from a submaximal lifted load and repetition count.

Fitness & sport↗

Session RPE Load Calculator

Record a simple session-duration and perceived-effort workload score.

Fitness & sport↗

Load From One Rep Max Percentage Calculator

Translate a chosen fraction of an entered maximum into a load amount.

Fitness & sport↗

Riegel Race Time Predictor

Estimate a different-distance race time with an explicit endurance-scaling exponent.

Fitness & sport↗

Running Step Length Calculator

Relate average running speed and cadence to step length.

Fitness & sport↗

Bicycle Gear Inches Calculator

Compare bicycle gearing through effective wheel-diameter gearing units.

Fitness & sport↗

Bicycle Gear Development Calculator

Find distance travelled per complete crank revolution for a bicycle gear.

Fitness & sport↗

Route Climbing Density Calculator

Summarise how much total climbing is present per kilometre of a route.

Astronomy & space↗

Magnitude Flux Ratio Calculator

Compare received flux from a difference in astronomical magnitudes.

Astronomy & space↗

Magnitude Difference From Flux Calculator

Convert an astronomical flux ratio into a magnitude difference.

Astronomy & space↗

Distance From Modulus Calculator

Recover astronomical distance from an entered distance modulus.

Astronomy & space↗

Redshift From Wavelength Calculator

Compare an observed spectral wavelength with its rest wavelength.

Astronomy & space↗

Observed Wavelength From Redshift Calculator

Find observed wavelength for a stated rest wavelength and redshift.

Astronomy & space↗

Orbital Period From Mu Calculator

Find orbital period from central gravitational parameter and circular-orbit radius.

Astronomy & space↗

Surface Gravity From Mu Calculator

Estimate gravity at a spherical body’s surface from its gravitational parameter.

Astronomy & space↗

Elliptical Orbit Eccentricity Calculator

Find orbital eccentricity from extreme orbital distances.

Astronomy & space↗

Orbit Semi Major Axis Calculator

Find an ellipse’s semi-major axis from periapsis and apoapsis distances.

Astronomy & space↗

Telescope True Field Calculator

Estimate sky field of view from apparent eyepiece field and telescope magnification.

Education & study↗

Required Future GPA Calculator

Find the average grade points needed on future credits to reach a cumulative GPA target.

Education & study↗

Pass Marks Needed Calculator

Translate a chosen percentage pass boundary into whole marks.

Education & study↗

Negative Marking Exam Score Calculator

Calculate an exam score under an entered correct-answer reward and wrong-answer penalty.

Education & study↗

Pages Per Day Study Calculator

Spread remaining reading pages over a chosen number of study days.

Education & study↗

Reading Completion Days Calculator

Estimate whole days needed to finish a page count at a planned daily rate.

Education & study↗

Word Count From Pages Calculator

Translate page count into approximate words using a chosen formatting density.

Energy & environment↗

Area Normalised Insulation R Value Calculator

Find thermal resistance per unit area from insulation thickness and conductivity.

Energy & environment↗

U Value From R Value Calculator

Convert an entered total thermal resistance into a heat-transmittance coefficient.

Energy & environment↗

Heat Loss From U Value Calculator

Estimate steady heat transfer through an envelope area using an overall U-value.

Energy & environment↗

Heating Fuel Input Calculator

Estimate input fuel energy for a useful-heating demand.

Energy & environment↗

Heat Pump Electricity Calculator

Estimate heat-pump electricity from delivered heat and an assumed COP.

Energy & environment↗

Water Heating Cost Calculator

Estimate energy spending for a water-temperature increase under a stated efficiency.

Energy & environment↗

Building Energy Intensity Calculator

Normalise entered building energy use by floor area.

Energy & environment↗

Solar Panel Count Calculator

Convert a nominal solar-array power target into whole panel count.

Energy & environment↗

Solar String Open Circuit Voltage Calculator

Add chosen design open-circuit voltages for a series solar string.

Energy & environment↗

Solar Parallel Short Circuit Current Calculator

Sum short-circuit current assumptions for equal parallel solar strings.

Energy & environment↗

Solar Battery Charging Hours Calculator

Estimate equivalent constant-power solar hours to replace a battery-energy amount.

Energy & environment↗

Stored Water Supply Days Calculator

Estimate how long usable stored water lasts at a fixed daily withdrawal.

Date & time↗

Time Zone Converter

Convert a local date and time between named time zones using the browser’s time-zone rules.

Date & time↗

Time Calculator

Add or subtract signed durations written as hours, minutes and optional seconds.

Date & time↗

Add Months to Date Calculator

Move a civil date by whole calendar months with an explicit end-of-month rule.

Date & time↗

Add Years to Date Calculator

Move a Gregorian date by whole years with leap-day clamping.

Date & time↗

Weekend Days Between Dates Calculator

Count Saturdays and Sundays in a start-inclusive, end-exclusive calendar interval.

Date & time↗

Business Days Excluding Holidays Calculator

Count weekdays while excluding a holiday-date list supplied by you.

Date & time↗

Calendar Months Between Dates Calculator

Find the signed difference between two Gregorian month labels.

Statistics↗

Z Test P Value Calculator

Find an approximate normal-model p-value from a supplied z statistic and a chosen tail.

Statistics↗

Normal Mean Confidence Interval Calculator

Find a symmetric normal-model interval from a mean, known population deviation and chosen critical value.

Unit converters↗

Millilitres to US Fluid Ounces Converter

Convert millilitres to explicitly US customary fluid ounces.

Unit converters↗

US Fluid Ounces to Millilitres Converter

Convert US liquid fluid ounces into millilitres.

Unit converters↗

Centimetres to Feet and Inches Calculator

Express a non-negative height as whole feet and a decimal inch remainder.

Unit converters↗

Feet and Inches to Centimetres Calculator

Convert a mixed feet-and-inches measurement into centimetres.

Health & wellbeing↗

Pregnancy Due Date Calculator

Estimate a pregnancy due date from the last menstrual period or a known conception date.

Health & wellbeing↗

Ovulation Calculator

Estimate an ovulation date and an illustrative fertile window from a regular menstrual cycle.

Health & wellbeing↗

Period Calculator

Estimate the next three period start dates from a typical regular cycle length.

Health & wellbeing↗

Body Fat Percentage Calculator

Estimate adult body fat percentage using the BMI-based Deurenberg equation, age and sex coefficient.

Health & wellbeing↗

Macro Calculator

Convert your chosen daily calorie amount and macronutrient percentages into grams of protein, carbohydrate and fat.

Money & finance↗

Mortgage Overpayment Calculator

Compare mortgage payoff time and interest with and without a fixed extra monthly principal payment.

Money & finance↗

Debt Snowball vs Avalanche Calculator

Compare payoff time and interest for multiple debts using snowball and avalanche repayment strategies.

Money & finance↗

Retirement Calculator

Project retirement savings, inflation-adjusted spending needs and a modelled funding gap.

Fitness & sport↗

Target Heart Rate Calculator

Estimate adult moderate and vigorous exercise heart-rate zones using the age-predicted maximum method.

Money & finance↗

Loan Interest Rate Calculator

Find the implied nominal annual interest rate from principal, monthly payment and payment count.

Money & finance↗

Currency Converter

Convert currencies using a rate you enter, with an option to fetch a dated indicative reference rate.

Money & finance↗

Take Home Pay Calculator

Calculate net pay from gross pay and tax, pension and other deductions that you enter for the same pay period.