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Random Number Generator

Free random number generator. Generate 1 to 100 random numbers in any range. Integers or decimals, unique values, sorted output. Uses Web Crypto API for true randomness.

Decimals:
Count
Sum
Average
Range
Click Generate to get random numbers

How to use the Random Number Generator

  1. Set your range — enter the minimum and maximum values in the toolbar fields. The default is 1 to 100, but any range works.
  2. Choose how many numbers — click one of the count buttons (1, 5, 10, 25, or 50) to control how many values are generated per click.
  3. Pick your options — enable Unique to avoid duplicates, Sort ascending to order results, or select decimal precision (0–3 places).
  4. Generate and use — click Generate, then copy individual numbers or click Copy All to grab the full list.

What makes it truly random

Most websites use Math.random() — a fast but predictable algorithm that generates numbers from a fixed seed. It's fine for games, but it isn't cryptographically secure and can theoretically be predicted if someone knows the seed.

This tool uses crypto.getRandomValues() — the same API browsers use for encryption. It pulls entropy from hardware sources like mouse movement, CPU timing, and network activity, making results genuinely unpredictable. Every click is statistically independent from the last.

For the Unique mode, we apply a Fisher-Yates shuffle over the integer range, guaranteeing no duplicates without sacrificing randomness. See related tools: Random Animal Generator and Random Name Generator.

Common uses for random numbers

  • Games and tabletop RPGs — roll dice with any range, not just 1–6 or 1–20. Set min=1, max=12 for a d12, or any custom range your game needs.
  • Statistics and sampling — pick random indices from a dataset, generate test data, or create random samples for analysis.
  • Raffles and giveaways — assign participants numbers and use the generator to pick a fair, verifiable winner.
  • Password and PIN generation — generate random digits as part of secure credentials. For full passwords, try the Password Generator.
  • Software testing — produce random inputs to stress-test functions, seed fuzzing tools, or populate databases with realistic-looking data.

Frequently Asked Questions

Is this truly random?

Yes — the generator uses the Web Crypto API (crypto.getRandomValues()), which provides cryptographically secure pseudorandom numbers. It is not predictable like Math.random().

What is the maximum range?

You can set any integer range — there is no hard maximum. For unique number generation, the range must be at least as large as the count you want to generate.

Can I generate decimal numbers?

Yes — set decimals to 1–6 to generate floating-point numbers. The result is rounded to the specified number of decimal places.

What does Unique mean?

When enabled, no number appears twice in the batch. This is equivalent to drawing numbers without replacement from the range.

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