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Random Number Generator

Generate fair random numbers by specifying the range, count, uniqueness, integer/decimal, and sort order. Uses cryptographically secure randomness. Perfect for lotteries and picking turns.

Last updated: 2026/10/16 Random Feedback & bug reports
Settings
Results

How to Use

1

Enter range and count

Set the minimum and maximum to define the range, and how many numbers to generate. Choose integer or decimal.

2

Set options

Choose whether duplicates are allowed (turn off for lotteries) and the sort order (ascending or descending).

3

Generate and copy

Press "Generate" to see the results, then copy them with one click using the copy button.

About the Random Number Generator

A web tool that generates a chosen quantity of random numbers within a chosen range. It uses the browser-native crypto.getRandomValues (a cryptographically secure pseudo-random number generator), so the results are fair and free of bias. Everything runs in your browser; your inputs and results are never sent to any server.

Features

  • Fair RandomnessPowered by crypto.getRandomValues with modulo-bias removal for unbiased results.
  • Flexible OptionsFreely combine range, count, integer/decimal, uniqueness, and sort order.
  • Unique DrawsTurn off duplicates for fair lotteries, raffles, and winning-number draws.
  • Privacy FirstAll processing happens in your browser. Nothing is sent to any server.

Use Cases

  • Picking winning numbers for lotteries and raffles
  • Deciding turns, duties, or seating order
  • Selecting sample numbers for surveys
  • Adding randomness to games and events
  • Creating test data and dummy values

FAQ

Are the generated numbers truly random?
They are produced with the browser-native crypto.getRandomValues, a cryptographically secure pseudo-random number generator. We also remove modulo bias, so every value in the range has an equal chance of appearing, giving you fair random numbers.
What does "No duplicates" mean?
It ensures the same value never appears twice in the results. For example, generating 3 numbers from 1-10 without duplicates always yields three different numbers. This is useful for lotteries where a number should not be drawn twice. Note that you cannot request more numbers than there are integers in the range.
Can it generate decimal numbers?
Yes. Choose "Decimal" as the number type and set the number of decimal places (0-10) to generate decimals within your range. Handy for probability or ratio simulations.
How many numbers can I generate at once?
Up to 10000 numbers at a time. Generating very large amounts may slow the browser slightly, but everything is processed on your own device.
Are the generated numbers stored on a server?
No. Your settings and results are never sent to or stored on any server. All processing happens locally in your browser, so you can use it with confidence.
Can I use it on my smartphone?
Yes. It works on all devices including smartphones, tablets, and PCs. No installation or registration required.

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