🧮 Math
Random Number Generator
Generate one random number, a list, or a unique set with no repeats. Any range.
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How random numbers are generated
This tool uses Math.random() - JavaScript's built-in cryptographically-seeded pseudo-random number generator. For most everyday purposes (games, sampling, decisions) this is more than sufficient. For cryptographic security, use a dedicated CSPRNG.
Unique numbers (no repeats)
When "No repeats" is enabled, the tool uses a Fisher-Yates shuffle to pick N unique numbers from the range. This requires the range to contain at least N numbers (e.g. you can't pick 10 unique numbers from a range of 1–5).
Common uses
Random number generators are used for: lottery number picking, sampling data, random assignment in experiments, board game decisions, password generation, and statistical simulations.