Randomantic How to use the random number generator
- Set your minimum and maximum — both ends are included in the draw.
- Choose how many numbers you need at once.
- Tick No repeats if each number must be unique.
- Click Generate. Click again for a fresh draw any time.
Common uses
Random numbers settle things fairly: picking a raffle or giveaway winner by ticket number, choosing who goes first, generating lottery-style picks, selecting a random sample for a survey, rolling for tabletop games when you've lost the dice, or picking a random page, row, or seat. Setting the range to 1–2 even gives you a coin flip, and 1–6 a classic die.
Both ends are included
A range of 1 to 10 here can return 1 and can return 10 — the endpoints are part of the draw. This sounds obvious, but it is the single most common mistake in home-made random number code, where the top of the range quietly never comes up. If you are drawing raffle tickets numbered 1 to 250, enter exactly 1 and 250; the holder of ticket 250 has the same chance as everyone else.
With repeats or without
The No repeats option is the difference between drawing numbers from a hat and putting each one back before the next draw. Leave it off and the same number can come up twice in one batch, which is correct for things like dice rolls, where each roll is independent. Turn it on for anything where a duplicate would be meaningless — raffle winners, lottery-style picks, choosing five different questions from a bank of fifty.
One constraint follows from that: you cannot draw more unique numbers than the range contains. Asking for ten unique numbers between 1 and 5 is impossible, not merely unlucky.
Why you should not pick the number yourself
Ask a room to "think of a number between 1 and 10" and the answers cluster hard on 7, with almost nobody choosing 1 or 10. Humans avoid the edges, avoid round numbers, and avoid repeats that feel insufficiently random — which is precisely why a human-chosen number is a bad way to run anything that needs to be fair. The whole value of a generator is that it has no taste.
How random is it, really?
This page uses your browser's built-in random number generator. It is a high-quality pseudo-random algorithm: the output is evenly distributed and unpredictable for any practical purpose, which makes it entirely appropriate for raffles, games, sampling, and deciding who buys lunch. It is not cryptographically secure, meaning it should not be used to generate anything that protects an account or money. For those, use the password generator or the PIN generator, which both draw from your browser's secure crypto source instead.
Shortcuts worth knowing
- 1 to 2 is a coin flip — though the coin flip is more satisfying.
- 1 to 6 is a standard die; the dice roller handles multiple dice and totals.
- 1 to 100 with no repeats, five at a time, is a quick random sample for spot-checking records.
- 0 to 1 settles a yes/no with the least ceremony possible.
Drawing names rather than numbers? The wheel spinner and the lucky draw picker take a list of entries directly.