Random Number Generator

Set a minimum and maximum, choose how many numbers you want and generate them. You can allow or forbid repeats, choose whole numbers or decimals, and sort the list.

Numbers come from your browser's cryptographic random source, so they are unbiased and unpredictable enough for games, raffles and sampling.

How random number generator works

Whole numbers are drawn with rejection sampling, which avoids the slight bias that a simple modulo would introduce. With “no repeats” selected, values are drawn until enough distinct ones have been found, so you cannot ask for more unique numbers than the range holds.

Both ends of the range are included. A range of 1 to 6 works like a die.

The formula

Whole number in [min, max]  =  min + random integer in [0, max − min]
Distinct values available  =  max − min + 1

Worked example: a raffle and a dice roll

Six unique numbers from 1 to 49: set count to 6, range 1 to 49, and turn repeats off.

A dice roll: min 1, max 6, count 1. Ten rolls: count 10 with repeats allowed.