24 FOCUSED TOOLS
Descriptive statistics calculators
Summarise location, dispersion and standardised differences.
Choose the right calculation
The mean, median, range and standard-deviation tools accept variable-length lists with their limits stated. Choose a sample or population denominator appropriately. A summary statistic does not validate the sampling process or explain causation.
Find a tool for your question
Arithmetic Mean Calculator
Find the arithmetic mean of a variable-length list of numbers.
Weighted Mean Calculator
Combine three values using non-negative weights.
Median Calculator
Find the median of a variable-length numeric dataset.
Data Range Calculator
Find the difference between the largest and smallest values in a dataset.
Population Standard Deviation Calculator
Find population standard deviation from a list of numeric observations.
Sample Standard Deviation Calculator
Estimate sample standard deviation from a variable-length numeric list.
Z Score Calculator
Express a value’s distance from the mean in standard deviations.
Coefficient of Variation Calculator
Express a standard deviation relative to a positive mean.
Relative Error Calculator
Compare absolute measurement error with a positive reference value.
Root Mean Square Calculator
Calculate RMS for four equally weighted observations.
Geometric Mean Calculator
Find the geometric mean of three positive values.
Harmonic Mean Calculator
Find the harmonic mean of two positive values.
Pooled Standard Deviation Calculator
Combine two sample deviations under a common-variance assumption.
Cohens D Calculator
Calculate a mean difference standardised by a supplied pooled deviation.
Statistics Calculator
Summarise a numeric dataset with its count, mean, median, minimum and maximum.
Mode Calculator
Find the most frequent value or tied values in a numeric dataset.
Percentile Calculator
Find a dataset percentile using inclusive linear interpolation.
Interquartile Range Calculator
Measure the spread of the middle half of a dataset.
Percentile Rank Calculator
Find the percentage of supplied observations strictly below a chosen value.
Population Variance Calculator
Find population variance for a variable-length numeric dataset.
Sample Variance Calculator
Estimate variance using N minus one for a supplied sample.
Mean Absolute Deviation Calculator
Find mean absolute distance from the arithmetic mean.
Median Absolute Deviation Calculator
Find the median absolute distance from the dataset median.
Trimmed Mean Calculator
Average a dataset after trimming equal whole-number counts from both tails.
Should I use sample or population standard deviation?
Use population deviation for the complete population being described. Use the sample form when estimating variability from a sample under suitable assumptions.
Useful next steps in other categories
Weighted Percentage Calculator
Combine two percentages using their actual group sizes.
Test Grade Percentage Calculator
Convert earned marks into a percentage of available marks.
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