Calculate the factorial of a non-negative integer n! — the product of all positive integers from 1 to n. Fundamental in combinatorics, probability, and series expansions.
Enter your values below
How this calculator works
The factorial of n (written n!) is the product of all positive integers from 1 to n. By definition, 0! = 1 and 1! = 1. For example, 5! = 5 × 4 × 3 × 2 × 1 = 120.
Common questions about this calculator
