Factorial Calculator

Calculate n! (n factorial), the product of all positive integers up to n, commonly used in combinatorics and probability.

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n!
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Formula

n! = n × (n−1) × (n−2) × ... × 1

Learn How This Works

GCD, LCM, Permutations, and Combinations Explained

The Euclidean algorithm behind GCD/LCM, and the factorial math behind permutations and combinations.

Frequently Asked Questions

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