Factorial Calculator
n! Result
10!
3,628,800
Digits in Result
7
Trailing Zeros
2
Permutations & Combinations
Permutations P(n,r)
720
Combinations C(n,r)
120
What is a Factorial?
The factorial of a non-negative integer n, denoted n!, is the product of all positive integers less than or equal to n. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120. By convention, 0! = 1.
Permutations and Combinations
Permutations P(n,r) = n! / (n-r)! - The number of ways to arrange r items from n items where order matters.
Combinations C(n,r) = n! / (r! x (n-r)!) - The number of ways to choose r items from n items where order doesn't matter.