What kind of UUID does this generate?

Version 4 (random) UUIDs, the most common kind. They are produced with the browser's cryptographically secure random generator, so they're suitable for database keys, request IDs and idempotency keys.

What is the chance of a collision?

Negligible. A v4 UUID has 122 random bits, so you would need to generate billions per second for many years before a duplicate became likely. For practical purposes they are unique.

Is a UUID the same as a GUID?

Yes — GUID (Globally Unique Identifier) is Microsoft's name for the same 128-bit UUID format. The values generated here work anywhere a GUID is expected.

UUID Generator

Generate cryptographically strong version-4 UUIDs (GUIDs) — one or up to a thousand at once, with uppercase and no-hyphen options. Runs entirely in your browser.

How many

Uppercase Remove hyphens

UUIDs

What a UUID is

A UUID (Universally Unique Identifier), also called a GUID, is a 128-bit value written as 32 hex digits in the pattern 8-4-4-4-12. Version 4 UUIDs are almost entirely random, which makes them ideal as primary keys, request and trace IDs, idempotency keys, file names and any place you need an identifier that won't clash without a central authority handing them out.

Strong randomness, generated locally

These use your browser's crypto secure random source — the same primitive used for cryptographic keys — so they're unpredictable, not just "random enough". Generating thousands at once is handy for seeding a database or load test.

Private by design. UUIDs are generated on your device and never transmitted. Nothing is uploaded.

Frequently asked questions

What version is generated?

Version 4 (random), the most widely used, via the browser's secure random generator.

Could two ever collide?

For all practical purposes, no — 122 random bits make duplicates astronomically unlikely.

UUID vs GUID?

Same thing — GUID is Microsoft's name for the identical format.

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