Generators · Free Tool
Random Number Generator
Generate one or many random integers or decimals in a custom range, with optional no-duplicates and sorting.
About this tool
Set a minimum and maximum, choose how many numbers you want, and generate cryptographically random integers or decimals instantly. Turn on "no duplicates" to draw a unique set without repeats (useful for raffles and sampling), and sort the result ascending, descending, or leave it in generation order.
Numbers are generated using the browser's crypto.getRandomValues — the same cryptographically secure source used by this site's password generator — rather than Math.random, so the distribution is unbiased even for security-adjacent uses like drawing lottery numbers or picking a random winner.
Common uses
- Draw unique raffle or giveaway winner numbers with no duplicates
- Generate a random sample of IDs or test data within a specific range
- Simulate dice rolls, lottery draws, or randomized assignment for a game or study
Frequently asked questions
How is randomness generated — is it truly random?
The tool uses crypto.getRandomValues, a cryptographically secure pseudo-random number generator built into every modern browser, seeded from the operating system's entropy source. It is suitable for contest drawings, sampling, and other uses where Math.random's weaker, predictable output would be a problem.
What happens if I ask for more unique numbers than the range allows?
The tool caps the request and tells you the maximum possible — for example, you can't draw 20 unique numbers from a range of 1 to 10, since only 10 distinct values exist.
Can I generate decimals, not just whole numbers?
Yes — switch to decimal mode and set how many digits after the decimal point you want; the no-duplicates option still applies to the rounded values shown.
Is my data uploaded to a server?
No. This tool runs entirely in your browser using JavaScript — nothing you type is transmitted, logged, or stored anywhere. You can even use it offline once the page has loaded.