随机数字

A range, not a hundred typed lines

Numbers are the one case where typing the list is obviously the wrong way in. Give the generator a start, an end and a step, and it builds the wheel: 1 to 100, or 5 to 50 in fives, or 2000 to 2025 for a year.

The step is the part people forget they want. Drawing a raffle ticket from every fifth number, picking an even number, choosing a decade — all of them are a range with a step, and all of them are tedious to type out.

Whether a number can come up twice

This is the question that separates the two jobs numbers get used for, and the wheel asks it directly rather than burying it in a mode name.

Leave repeats on and every spin draws from the whole range, so 17 can come up twice in a row. That is what you want when the numbers are answers — a dice roll, a random pick, a starting player.

Turn repeats off and each drawn number comes off the wheel. That is what you want when the numbers are things: seats, tickets, prizes, rounds. It works by removing the number, not by re-rolling until something new appears — a wheel that quietly re-rolled would be showing you one set of odds while running another, which is the behaviour this whole site exists to argue against.

How this differs from a random number generator

A generator gives you a number. This gives you a number in front of other people.

That difference is the entire reason to use a wheel: the draw is watchable, it takes long enough to be witnessed, and nobody has to trust that you did not press refresh. For a raffle drawn in a room, that is worth more than the milliseconds a generator saves. For a number you need inside a script, it is worth nothing — use a generator.

The randomness underneath is the same quality either way. Your browser's cryptographic generator, with the biased tail of values discarded rather than folded back in, which is documented in full rather than asserted.

Large ranges

A range can build up to a thousand numbers. Past thirty, the wheel shows thirty sectors and the rest share the last one, labelled with how many are behind it — the draw still runs across every number in the range, and a folded number that wins is named like any other.

If you need more than a thousand, split the range. The limit is refused rather than silently trimmed, because a wheel that quietly dropped the top half of your range would be wrong in a way you could not see.