Random Number Generator

Generate one or many random integers or decimals within a range, with or without repeats.

How random is this?

This generator uses your browser's built-in pseudo-random number generator, which produces numbers that are statistically indistinguishable from true randomness for everyday purposes — picking a raffle winner, rolling for a game, shuffling a list. It's not suitable for cryptography or security-sensitive uses, which require specialized random sources.

Integers vs. decimals

Integer mode returns whole numbers only, evenly spread across your range. Decimal mode returns numbers with a fractional part, rounded to however many digits of precision you choose — useful for things like simulating measurements or generating test data.

With duplicates disallowed, the number of unique integers you can request is capped by the size of your range — you can't generate 50 unique numbers from a range of only 20 possible values.

Common questions

Why would I disallow duplicates?

Useful whenever each result needs to be unique — assigning raffle numbers, shuffling a deck, or picking several different winners from a pool without repeats.

Does refreshing give a different result?

Yes — every time you click Generate, a fresh set of random numbers is produced. Nothing is cached or remembered between runs.

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