Factorial calculator
Calculate n!, the product of the positive integers up to n.
Formula
n! = 1 × 2 × … × n; 0! = 1
Nonnegative integer n = 10
How to use
- Enter a whole number from 0 to 170.
- Read the factorial.
- Use scientific notation for large results.
Examples
- 5! = 120.
- 10! = 3628800.
Frequently asked questions
Why is 0! equal to 1?
It is the empty-product convention and makes the recurrence n! = n × (n−1)! consistent.
Are negative or fractional values allowed?
No. This tool uses the factorial of nonnegative integers.
Are large answers exact?
Large factorials are floating-point approximations; values above 170 would overflow.
Sources
Updated: