Lookup
Tools for looking up information about various entities.
31187520038020403225989603819816Quickly evaluate factorials, permutations, combinations (with/without repetition), multiset permutations, and binomial probabilities. Exact integer results use BigInt within safe thresholds; beyond those, Stirling and logarithmic approximations provide digits and magnitudes without freezing your browser.
For very large inputs, the tool reports digit counts and log10 values rather than full integers.