Free Cryptographically Secure Random Number Generator

How to Use This Random Number Generator

1. Set your Minimum value (default is 1).
2. Set your Maximum value (default is 100).
3. Click Generate Number.
4. Watch the animated result reveal your cryptographically secure random number.
5. Click again for a new result — each press is completely independent.

Key Features

• Cryptographically secure — uses the Web Crypto API, not Math.random().
• Custom range — set any minimum and maximum integer values.
• Animated result — satisfying slot-machine reveal on every generation.
• Instant results — no loading, no server round-trips.
• Completely free — unlimited generations, no account needed.
• Works on any device — mobile, tablet, and desktop.

Use Cases

Random Number Generator for Giveaways and Contests

Set your maximum to the number of entrants and click Generate. The cryptographic security ensures every participant has an equal chance, making this tool reliable for social media giveaways, raffles, and classroom draws.

Online Random Dice Roller for Games and Tabletop RPGs

Simulate any standard die by setting your range: 1–6 for a d6, 1–20 for a d20, or any custom range for homebrew mechanics. Generate as many rolls as you need without physical dice.

Pick a Random Number for Lottery Selection

Generate lottery numbers within any pool size (e.g., 1–49 or 1–70). Click multiple times to build a full set of picks. The secure entropy source means results are not predictable or biased.

Random Number Generator for Research and Statistical Sampling

Researchers and statisticians can use this tool to randomly select sample IDs, assign participants to groups, or generate random seeds for reproducible experiments. Once you have your sample, use the average calculator to compute the mean, median, and standard deviation of your results.

Random Decision Maker for Everyday Choices

Can't decide between two options? Set the range to 1–2 and let randomness settle it. Use it to pick a restaurant (1–10), assign chores, or break any tie fairly.

How Random Number Generators Work

Computers typically use Pseudo-Random Number Generators (PRNGs), which are algorithms that produce sequences of numbers that look random but are determined by an initial seed value. Our tool uses a Cryptographically Secure PRNG (CSPRNG) via the Web Crypto API, ensuring that numbers are sourced from genuine hardware entropy and are statistically unpredictable — suitable for any application where fairness or security matters.

Common Uses for RNG

• Contests and Giveaways: Fairly selecting a winner from a pool of entrants.
• Gaming: Simulating dice rolls or random event outcomes.
• Research: Selecting random samples for statistical studies.
• Cryptography: Generating initialization vectors and one-time values — the same secure entropy powers the password generator.