Factorial Calculator

Calculate n! (n factorial). Example: 5! = 120. Enter non-negative integer. Copy result.

Factorial n! = n × (n−1) × … × 1 for positive integer n. 0! = 1. Enter a non-negative integer. The calculator gives n!. Copy the result or Copy with labels.

Loading…

Advertisement

Examples

  • 5! = 120
  • 0! = 1
  • 10! = 3628800

FAQ

What is factorial?

n! = n × (n−1) × (n−2) × … × 1. By definition 0! = 1.

What is 5 factorial?

5! = 5 × 4 × 3 × 2 × 1 = 120.

Can I use decimals or negative numbers?

No. Factorial is defined only for non-negative integers (0, 1, 2, …).

What is the largest n I can enter?

Very large n (e.g. 100+) give huge numbers. The calculator may round or use scientific notation.

What is 0!?

0! = 1 by definition.

Advertisement