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Random Number Generator — Cryptographically Secure with Statistics

What random number do you need?

What This Does

Generate one or many cryptographically secure random numbers within any range — with optional unique (no-repeat) mode, batch generation up to 1,000 numbers, and statistical analysis of your results. This generator uses the browser's Web Crypto API for randomness, making it appropriate for raffles, sampling, security applications, and any use case where true unpredictability matters. Standard JavaScript Math.random() is a pseudorandom generator — predictable under certain conditions and not suitable for security-sensitive applications. The statistics panel shows the mean, median, min, max, and distribution of your generated batch — useful for verifying the numbers are uniformly distributed and for educational purposes. Common use cases include: random sampling for surveys, raffle and lottery drawings, randomizing a list for blind testing, and classroom activities where unbiased selection matters. The unique (no-repeat) mode ensures no number appears twice in a batch — essential when duplicates would invalidate the result, such as assigning students to groups or selecting winners from a fixed pool.

When Should You Use This?
  • Selecting random contest winners, raffle tickets, or prize draw participants fairly
  • Randomly assigning students to groups, seats, or presentation order without bias
  • Generating sample numbers for statistics homework or Monte Carlo simulations
  • Creating random data for software testing or database seeding
  • Picking a random number for games, tie-breakers, or decision-making
Example Scenario

A teacher has 28 students and needs to randomly call on 5 for a quiz question without bias. She generates 5 unique random numbers from 1 to 28 with no-repeats enabled. Results: 7, 19, 3, 24, 11. Students at those positions on her class roster are called. The unique mode ensures no student is selected twice — fair, instant, and requiring no manual shuffling.

🎲Random Number Generator

Cryptographically Secure Random Numbers

Generate random numbers using window.crypto — suitable for lotteries, raffles, simulations, and decision-making. Configure range, count, and uniqueness, then press Generate.

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