Tech
Random Number Generator
Generate random numbers within any range. Supports integers or decimals, single or many, with optional uniqueness.
Settings
Set a min/max and how many numbers you need, then click Generate.
Frequently Asked Questions about the Random Number Generator
Is this random number generator truly random?
It uses your browser's cryptographically secure random source (crypto.getRandomValues), so the output is unpredictable and unbiased - suitable for games, raffles, lottery picks, and statistical sampling. If your browser does not support that API, the generator falls back to Math.random, which is still fine for casual use but not cryptographic-grade.
Can I use this for a giveaway or contest?
Yes. Set the range to cover your entry count - for example 1 to 500 - then enable "integers only" and "unique values" and set the count to the number of winners you need. Each result will be a distinct entry number picked with equal probability.
What is the maximum range?
You can generate up to 1,000 numbers per run. The min and max can be any value, but integer results stay exact only up to about plus or minus 9 x 10^15 (JavaScript's safe-integer limit); beyond that you may see rounding past roughly 15 significant digits. For everyday ranges like 1 to 1,000,000 the results are exact.
Why does 'unique values' fail sometimes?
For integers, it fails when you request more unique numbers than the range contains - for example, 10 unique integers between 1 and 5 is impossible. For decimals (rounded to 6 places), it can also fail when the range is so narrow that the generator cannot find enough distinct values within its attempt limit.