Factorial Calculator

Math guide

How to use the Factorial Calculator

Calculate n factorial for whole numbers up to 170. The page also explains the factorial and shows a practical example: 8! equals 40,320.

  1. 1

    Enter your details

    Enter the values for the factorial calculator scenario you want to check.

  2. 2

    Check the calculation

    Review the result alongside the factorial: n! = n x (n - 1) x ... x 1.

  3. 3

    Compare scenarios

    Change one or more inputs to see how they affect the factorial Calculator result before you use the estimate.