Random Number Generator

Picking a number without bias

People are famously bad at choosing numbers at random. Asked for a number between 1 and 10, far too many say 7; asked between 1 and 100, answers cluster on numbers with two odd digits. If the number decides something that matters — a raffle, a sample, who goes first — that bias is worth removing.

This generator uses your browser's cryptographic random source when it is available, and draws uniformly across the range so every value is equally likely.

Repeats, and when to turn them off

Allowing repeats models rolling a die several times: each draw is independent, and getting the same number twice is normal. Turning repeats off models drawing tickets from a hat without putting them back, which is what you want for a raffle or for picking distinct sample rows.