Random Number Generator

Generate random integers or decimals in any range, in batches with optional uniqueness. Numbers come from the browser's cryptographically secure random source, so everything is generated locally and instantly.

By default results are unique. For decimals, uniqueness is judged at the selected precision. The maximum count is 10000 — generate in batches for more.

How to use

  1. Enter a minimum and maximum value (negative numbers and decimals are fine), then set how many numbers you need (up to 10000).
  2. Duplicates are off by default, so every result is unique. Tick "Allow duplicates" if equal outcomes are acceptable.
  3. Pick "Integer" or "Decimal"; for decimals you can also choose 1–6 decimal places.
  4. Click "Generate" to see the results, then "Copy all" to copy the whole list at once, or "Clear" to start over.

FAQ

Are the numbers truly random?
Yes — values are produced with crypto.getRandomValues(), the browser's cryptographically secure random source, which is far stronger than plain Math.random(). Generation happens entirely on your device with no server involved.
Why am I told that not enough unique numbers are available?
When duplicates are disabled every result must differ, so the count cannot exceed the number of distinct values inside the range (integers within the interval, or decimals distinguishable at the chosen precision). Widen the range, reduce the precision, or enable duplicates to fix it.
What is the maximum number of results per batch?
The per-batch limit is 10000 to keep the page responsive. If you need more, generate several batches with adjusted parameters or switch to allowing duplicates.

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