UUID v4 Generator

A UUID (universally unique identifier) is a 128-bit value with so much randomness that you can generate them on any machine, at any time, without coordination — and still never expect a collision. That property makes UUIDs the default choice for database primary keys, request IDs, idempotency keys, file names and distributed tracing.

This generator produces version 4 (random) UUIDs using the browser's cryptographically secure random number generator — the same crypto.randomUUID() API used in production code, not a weak Math.random() approximation. Generate one or hundreds at a time, switch to uppercase, or strip the hyphens when a system demands a bare 32-character hex string.

Typical moments you'll want this page: seeding a database fixture, filling in an API request that requires a client-generated ID, writing tests, or quickly grabbing a unique string for a config file. Every UUID is generated locally in your browser and copied straight to your clipboard — nothing is sent to or stored on any server.