ToolFerry
Calculators

Random Number Generator

Generate one or many random numbers in a custom range, with the option to disallow duplicates. Uses the Web Crypto API for cryptographically strong randomness.

Last updated July 19, 20263 min read
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How to use

  1. 1

    Set the range

    Enter the smallest and largest allowed values.

  2. 2

    Choose how many

    Generate a single number or a whole list at once.

  3. 3

    Toggle duplicates

    Turn duplicates off for raffles, drawings, and lotteries.

Benefits

  • Uses crypto.getRandomValues for true unpredictability.
  • Optional unique-only mode for fair drawings.
  • Copy the entire result set with one click.
  • Runs entirely offline in your browser.

Common uses

  • Raffles, giveaways, and drawings
  • Randomly picking questions or team members
  • Testing and seeding data
  • Games and decision-making

Frequently asked questions

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