Factorial Calculator
The factorial of n.
Factorial Calculator
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Calculated instantly
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What This Calculator Does
The Factorial Calculator computes n! for any positive integer. The factorial of n is the product of all positive integers from 1 to n. Factorials are fundamental in probability, combinatorics, and series expansions.
How It Works
n! = n x (n-1) x (n-2) x ... x 2 x 1. By convention, 0! = 1.
Example
7! = 7 x 6 x 5 x 4 x 3 x 2 x 1 = 5,040.
Formula
n! = n x (n-1) x ... x 1Reading the Results
n!
The factorial of n, the product of all integers from 1 to n.
Frequently Asked Questions
What is 0 factorial?
0! = 1 by convention. It ensures the combinatorial formulas remain consistent.
How big can factorial go?
170! is the largest factorial that fits in a standard JavaScript number. Beyond that, you need arbitrary-precision arithmetic.
Where are factorials used?
Probability, combinations, permutations, Taylor series expansions, and many areas of pure mathematics.