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Random Number Generator

Generate one or more random integers inside your chosen range with a satisfying rolling reveal.

Pick a range and generate

Set the lower and upper limits, optionally choose how many numbers to draw, and let the animation roll to the result.

Each number is generated independently, so duplicates can appear.

Show running average
Track the mean of all generated numbers across runs.

The range is inclusive, so both the lower and upper limits can be returned.

Generated number

Every draw rolls in from a fresh random starting point before landing on the final value.

Ready for the first draw

Enter a range above and press Generate to reveal your random number.

How it works

A quick guide to using the generator and understanding the random draw.

How to use this tool

  1. Enter the lower limit and upper limit for the range you want to draw from.
  2. Open Advanced if you want more than one result, then choose any whole number from 1 to 20.
  3. Press Generate to roll the animation and reveal the final number or numbers.
  4. Use Copy results when you want to paste the generated values somewhere else.

How the random number is generated

Each result is a whole number selected from the inclusive range you entered, so the lower and upper limits are both valid outcomes.

When your browser supports the Web Crypto API, the generator uses that built-in random source and maps it into your chosen range. That gives each integer in the range an equal chance of being selected. If Web Crypto is not available, the tool falls back to Math.random().

If you generate multiple numbers at once, each draw is produced independently. That means repeated values are possible, which is useful when you want simple random picks instead of unique lottery-style combinations.