Factorial Calculator
Compute the factorial (n!) of a non-negative integer.
10
Yes
Formula
About this calculator
The factorial of a non-negative integer n, written n!, is the product of every whole number from 1 up to n. By definition 0! = 1. Factorials grow extremely fast and appear throughout combinatorics, probability, and series expansions.
This calculator multiplies the terms iteratively. Because standard floating-point numbers cap out around 1.8 × 10³⁰⁸, factorials above 170! overflow to infinity and are flagged. Results below 18! are exact integers; larger values are accurate floating-point approximations.
Frequently asked questions
There is exactly one way to arrange zero items (the empty arrangement), and defining 0! = 1 keeps formulas for permutations and combinations consistent.
171! is larger than the maximum value a double-precision number can hold, so it overflows to infinity. 170! is the largest factorial representable as a finite number.
They count the number of ways to arrange items (permutations) and appear in combinations, probability, and Taylor series in calculus.
Did this calculator help you?