Random number generator
Pick random whole numbers in a range, with or without repeats.
Uses your browser's cryptographic random generator. Not for prize draws that have legal requirements.
How this calculator works
Each number comes from crypto.getRandomValues, the same source browsers use for security keys, mapped evenly onto your range. With repeats off, any number already drawn is skipped.
Ideas: choose 1 to 6 for a die roll, 1 to 30 to pick a student, or 1 to 45, six numbers, no repeats, to see how unlikely any one combination is.
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