Factorial Calculator

What is a Factorial?

The factorial of a non-negative integer n, denoted by n!, is the product of all positive integers less than or equal to n.

Formula

n! = n × (n-1) × (n-2) × ... × 2 × 1

0! = 1 (by definition)

Applications

• Combinatorics and permutations
• Probability calculations
• Series expansions (Taylor series)
• Statistical distributions

Examples

5! = 5 × 4 × 3 × 2 × 1 = 120

10! = 3,628,800