When to use this calculator
Calculate the product of all positive integers up to a whole number. Only integers from 0 to 170 are accepted to stay within the numeric range.
Explore the algebra & number calculators for other questions in this topic. For a related calculation, use the Fibonacci Number Calculator: Find a term of the Fibonacci sequence using its recurrence.
PUTTING IT INTO PRACTICE
Factorial: a worked example
The values below are an illustrative example, not a recommendation. Replace them with measurements or assumptions that match your question.
| Input | Example value |
|---|---|
| Whole number | 5 |
| Result | 120 |
- Check the input labels and enter the example values above.
- Apply the relationship: n! = 1 × 2 × … × n; 0! = 1.
- The result is 120 , rounded for display.
How to interpret your result
Only integers from 0 to 170 are accepted to stay within the numeric range.
Identify whether the question asks for one term, a total or a count of possible selections. Sequences use a fixed difference or ratio. In counting problems, order and replacement determine the correct model.
Frequently asked questions
Do combinations and permutations count the same thing?
No. Combinations ignore the order of selection; permutations count different orders separately.
How do I use the factorial calculator?
Enter whole number. The result updates automatically. Use the units shown beside each input; the example values illustrate the method.
Which formula does this calculator use?
n! = 1 × 2 × … × n; 0! = 1.
What should I check before using the result?
Only integers from 0 to 170 are accepted to stay within the numeric range.
How are results rounded?
Scalar numbers display up to six decimal places, with scientific notation for very large or small values. Text, fraction, date and schedule outputs use the format described on the tool. Intermediate calculations use JavaScript floating-point arithmetic. Keep sensible precision for your measurements.
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