Random Number Generator

Generate one or many random numbers in any range — whole or decimal, with or without repeats — using a secure random source.

What is the Random Number Generator?

A random number generator picks numbers with equal probability. It is useful for draws, sampling, games and testing.

How does it work?

Numbers come from your browser’s cryptographically secure generator (Web Crypto) and are mapped uniformly onto your range. With “No repeats”, duplicates are skipped.

Formula

x = min + ⌊u × (max − min + 1)⌋, u uniform in [0, 1)

Example

Six unique numbers between 1 and 49 for a lucky draw.

Frequently asked questions

Are the numbers truly random?

They come from a cryptographically secure pseudo-random generator, which is suitable for draws and security-sensitive uses.

Related tools

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