ToolSink

UUID Generator

Generate cryptographically-random RFC 4122 v4 UUIDs in bulk.

What is the UUID Generator?

The UUID Generator produces RFC 4122 version-4 UUIDs — 128-bit random identifiers used for primary keys, request IDs and correlation IDs. Generate one at a click or a batch of hundreds for seed scripts and test fixtures.

Generation uses the browser's cryptographic random source (Web Crypto API), so IDs never pass through a server.

How to use the UUID Generator

  1. 1Choose how many UUIDs you need.
  2. 2Pick formatting options: with or without dashes, uppercase or lowercase.
  3. 3Click "Generate".
  4. 4Copy the whole list with one click or download it as a file.

Key features

  • RFC 4122 version-4 (random) UUIDs
  • Batch generation for seed data and fixtures
  • Uppercase, lowercase and dash-less variants
  • Cryptographically secure random source
  • Copy all or download as a file

Important notes

  • Version 4 UUIDs are randomly generated. Collisions are astronomically unlikely but not mathematically impossible.
  • A UUID is an identifier, not a secret — it is not meant to be used as a password or security token.
  • IDs are generated locally in your browser and are not logged or stored anywhere.

Frequently asked questions

Are the UUIDs really unique?

Version 4 UUIDs contain 122 random bits, so the collision probability is negligible for any real-world use.

Can I generate time-based UUIDs (v1/v7)?

Only v4 is currently supported.

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