Last updated 3 September 2026
With or without repeats
The default mode can produce the same number more than once, just like rolling a die several times can land on the same face twice. Turning on "no repeats" instead draws from the range without putting numbers back — which only works if the range is large enough to supply as many unique numbers as requested.
How the randomness here is produced
This generator draws from your browser's cryptographically secure random source rather than a simple arithmetic sequence. The practical difference is predictability: a basic pseudo-random generator produces a stream that can be reconstructed by anyone who learns its starting seed, whereas a cryptographic source is seeded from unpredictable system entropy and is not reproducible.
For picking a raffle winner or rolling dice, either would be fine. The distinction matters when the outcome has value attached to it and someone has a reason to game it — a prize draw, a random assignment in a study, or anything where the result needs to stand up to a challenge.
What people expect randomness to look like
Genuine randomness clusters, and this trips people up constantly. In twenty draws from 1 to 10 you should expect some numbers to appear three times and others not at all. A perfectly even spread would actually be evidence that the process is not random. The same instinct is why a run of four heads feels wrong when it happens roughly once in every sixteen sets of four tosses.
The related trap is the gambler's fallacy: a number that has not come up is not "due". Each draw with replacement is independent and has no memory of the ones before it. If you need every value to appear exactly once, that is drawing without replacement — a shuffle — and it is a different operation from repeated random picks.
Common questions
What does "unique" actually do?
It guarantees no number repeats in the result, the way drawing raffle tickets without putting them back works. It's only possible when the range has at least as many numbers as you're asking for — asking for 10 unique numbers from a range of 5 isn't possible, and the tool says so rather than guessing.
Is this good enough for something like a raffle or giveaway?
For everyday fairness, yes — it uses the browser's standard random number source, which has no memory or bias toward any number. For anything with real money or legal stakes, check what randomness standard is actually required.
Can the range include negative numbers?
Yes — minimum and maximum can be any whole numbers, positive, negative, or a mix, as long as the minimum isn't larger than the maximum.
Are these numbers genuinely random?
They come from your browser's cryptographically secure random source, which is seeded from unpredictable system entropy rather than a fixed formula. That makes the sequence non-reproducible, unlike a basic pseudo-random generator whose output can be recreated from its seed.
Why did the same number come up several times?
Because that is what randomness looks like. Over a small number of draws, clusters and gaps are expected — an evenly spread result would actually be the suspicious one. Each draw is independent, so a repeat is no less likely than any other value.
How do I get numbers with no repeats?
That is drawing without replacement, which is a different operation from repeated random picks. Generate a list covering the full range and shuffle it, then take values from the top. Repeated independent draws will always produce duplicates given enough attempts.