Random Number Generator
Generate random numbers in any range, with or without repeats, one or many at a time. Uses the browser cryptographic random source. Free.
Result
The result appears here as you type.
What this tool is for
Pick numbers in a range you set, with an option to forbid repeats for a lottery style draw. The values come from crypto.getRandomValues rather than Math.random, and rejection sampling keeps the distribution even instead of biasing the low end of the range.
How to use it
- Set the minimum and maximum.
- Choose how many numbers to draw and whether repeats are allowed.
- Generate, and draw again as often as you like.
Frequently asked questions
Is this suitable for a giveaway?
Yes. The source is the operating system entropy pool, unseeded and not reproducible, which is what makes a draw defensible.
Why not use Math.random?
It is a fast pseudo-random generator whose output is predictable from previous values and is explicitly not for anything that must be unguessable.