Random Number Generator
Generate random numbers in any range — one at a time or up to 1000 at once, with a no-repeat mode for fair draws. Everything runs locally in your browser with a cryptographically secure random source.
How to use
- Set your range with Min and Max — for example 1 to 100, or 1 to 6 for a die.
- Set Count to generate many numbers at once; turn on No repeats when every value must be unique.
- Click Generate, then Copy to grab the results. Leave Decimals above 0 if you need fractions.
- Type anything into Seed to get the same sequence every time — handy for tests and demos.
What it's good for
Classroom draws and raffles. Picking students, winners or teams with No repeats turned on guarantees nobody gets drawn twice — a fair, no-repeat random number picker for groups of any size.
Board games and dice. Set 1–6 for a die, 1–20 for D&D, or generate a whole set of throws at once when you don't have physical dice around.
Reproducible tests and simulations. Developers can enter a seed to replay the exact same sequence — useful for debugging sampling code, demos and Monte-Carlo experiments.
Notes & limits
Without a seed, numbers come from your browser's cryptographically secure random source (crypto.getRandomValues) with rejection sampling, so every value in the range is equally likely. A seed switches to a fast deterministic generator (mulberry32): reproducible, but not suitable for security or gambling. Ranges are limited to exact integers (below ±2⁵³), and you can generate at most 1000 numbers per click. Everything runs locally; nothing is uploaded.
FAQ
How do I generate random numbers without repeats?
Check "No repeats" and every generated number will be unique — perfect for raffles, bingo or picking students. Just make sure the range is at least as large as the count you ask for.
Can I generate multiple random numbers at once?
Yes. Set Count to anything from 1 to 1000 and all results appear in one list, ready to copy. Generating a batch uses the same unbiased algorithm as a single number.
Is this a cryptographically secure random number generator?
By default, yes — numbers come from crypto.getRandomValues, your browser's CSPRNG, with rejection sampling to remove bias. If you enter a seed, the generator switches to a fast deterministic algorithm for reproducibility, which is not cryptographically secure.
What does the seed option do?
The same seed always produces the same sequence for the same settings. It's meant for tests, demos and simulations where you need to replay results — leave it empty for fresh randomness.
Can I generate random decimals or a number between 1 and 100?
Set Min to 1 and Max to 100 for a classic 1–100 draw. For fractions, raise Decimals (up to 6 places) — the range stays uniform, just with finer steps like 0.01.
Is my input uploaded anywhere?
No. Generation happens entirely in your browser; your range, seed and results never leave your device, and no account is required.