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UUID / GUID Generator

Generate cryptographically random UUID v4 identifiers.

Runs in your browserNo account requiredNo uploadFree
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About UUID / GUID Generator

UUID Generator produces version 4 UUIDs — 128-bit identifiers in the canonical 8-4-4-4-12 hyphenated form, such as 9a3f6e72-8b1d-4c2e-9f4a-1e2c3d4b5a6f. UUID v4 is the everyday choice when a service needs a unique ID and you do not want to coordinate with anyone to get one: database row keys, idempotency keys, file names, request IDs, session identifiers.

Worked example: hit 'Generate' once and you get a single UUID; bump the count up and you can produce as many as a thousand at a time, ready to copy into a seed file or paste into a database column. Output options let you switch the casing or drop the hyphens, producing the plain 32-character hex string that some downstream systems prefer.

The randomness comes from the browser's Web Crypto API — crypto.randomUUID under the hood when available — not the much weaker Math.random. That matters: with 122 bits of true randomness per UUID, the chance of any two ever colliding, even at the scale of trillions of generations, is effectively zero. UUID v4 carries no embedded timestamp or MAC address (unlike v1), so it leaks nothing about the machine that created it. It is suitable as a unique ID; it is not, on its own, a secret authentication token.

Everything happens in your browser. The UUIDs you generate are not stored, logged, or shared, so they are safe to use as keys for sensitive resources straight away.

Frequently asked questions

Up to 1,000 at once. Larger batches are easy to compose by generating multiple times.

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