Random number generator
Fair random numbers in any range, or a random pick from your list.
How it works
- 01Set the lowest and highest number, and how many you want.
- 02Choose whether repeats are allowed, decimals, and sort order.
- 03Generate, then copy the results. Switch to "from a list" to pick items instead.
Questions
›How random are the numbers?
They come from your browser's secure random generator, crypto.getRandomValues, the same one used for encryption keys. To fit them to your range we use rejection sampling instead of a simple remainder, so every number in the range is exactly equally likely.
›Are the minimum and maximum included?
Yes. A range of 1 to 10 can give both 1 and 10.
›What does "no repeats" do?
Each number can come up only once, like drawing numbered balls from a bag without putting them back. It's handy for raffles and seating orders. You can't ask for more numbers than the range holds.
›How do decimals work?
Pick how many decimal places you want, from 1 to 6. Every value with that many places between your minimum and maximum is equally likely.
›Is my data uploaded anywhere?
No. This tool runs entirely in your browser, and Rounder never sends what you type or drop in to a server, ours or anyone else's. Once the page has loaded, along with any AI model the tool uses, it even works offline.