Random Number Generator

The Random Number Generator produces one or more random whole numbers within a range you choose, with the option to allow or block duplicate values.

How the numbers are generated

This generator uses your browser's built-in cryptographically secure random number source (crypto.getRandomValues) rather than the weaker Math.random(), mapped evenly onto your chosen range. When "no duplicates" is selected, numbers are drawn from a shrinking pool so no value repeats.

Example: Generating 5 unique numbers between 1 and 100 might produce: 7, 42, 63, 18, 91 — a new, unpredictable set every time you click Calculate.

Common uses

Random number generators are handy for raffles and giveaways, choosing sample sizes for statistics, generating test data, or just settling a decision. For data analysis on numbers you already have, see our Standard Deviation Calculator.

Related Calculators