Factorial & Permutation Calculator

Enter n (and r). Get n!, nPr, nCr using BigInt. Perfect for probability puzzles and coding challenges.

Tip: Click the banner to expand/collapse the full value. Use Sample to auto‑generate n and r. Toggle “Group digits” for readability.

BigInt used for exact results. Approximation available for very large n.
n! (Factorial)
digits: —
nPr (Permutations)
digits: —
nCr (Combinations)
digits: —
Calculations & Formulas

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