Factorial calculator
Calculate the factorial (n!) of a number, exact for large values.
Free factorial calculator
Calculate the factorial of a number (written n!). The factorial is the product of all positive integers up to n: for example 5! = 5 × 4 × 3 × 2 × 1 = 120. This tool handles very large results exactly using big integers, so even 100! is shown in full. Useful for combinatorics, probability and permutations.
FAQ
What is 0!? By definition, 0! = 1. How big can it go? Up to 2000! here, computed exactly.