Generate truly random numbers, dice rolls, coin flips, lists, UUIDs, and item pickers — all in your browser.
Generate a cryptographically secure random number between any two values using the Web Crypto API.
Math.random().
Most programming languages use a pseudo-random number generator (PRNG) like Math.random(), which produces numbers that look random but are deterministic — given the same seed, you'll always get the same sequence. This tool uses the browser's crypto.getRandomValues() API, which is a cryptographically secure PRNG (CSPRNG) seeded from true entropy sources like hardware noise, timing variations, and OS-level randomness. This makes it suitable for security-sensitive applications like key generation and token creation.
A UUID (Universally Unique Identifier) v4 is a 128-bit number formatted as xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx, where the 4 indicates version 4 (random) and y is one of 8, 9, a, or b (the variant bits). With 122 bits of randomness, the chance of collision is astronomically small — you could generate 1 billion UUIDs per second for 85 years before expecting a 50% chance of a single collision.