Factorial Calculator

Compute factorials, permutations, and combinations for quick combinatorics work.

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nPr

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nCr

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FAQ

What is a factorial? It is the product of a positive integer and all smaller positive integers down to `1`.
What is the difference between nPr and nCr? `nPr` counts ordered arrangements, while `nCr` counts unordered selections.
Can this page handle larger values? Yes. It uses browser `BigInt` arithmetic for many larger whole-number calculations.

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