Math
Factorial Calculator
Calculate the factorial of a non-negative integer.
Calculator
FACTORIAL
Calculate a factorial
Enter a whole number from 0 to 170.
YOUR RESULT
HOW IT WORKS
About This Calculator
The factorial of n, written n!, is the product of every positive integer from 1 through n. By definition, 0! equals 1.
Formula & Notes
n! = n × (n−1) × (n−2) × … × 1, with 0! = 1.
Results are estimates for general informational use and should not be treated as medical, financial, or professional advice where applicable.