UUID Generator
Generate random version 4 UUIDs (GUIDs) in bulk, with format options.
Runs in your browser — your data never leaves your device.
About the UUID Generator
A UUID (Universally Unique Identifier), also called a GUID, is a 128-bit ID used as database keys, file names, API request IDs and test data. Version 4 UUIDs are random, so they can be created anywhere without coordination and practically never collide.
How to use the UUID Generator
- Choose how many UUIDs you need.
- Choose the letter case and format (standard, no hyphens, braces, or quoted for code).
- Click Generate, then Copy or Download .txt.
How it works
A version 4 UUID has 122 random bits plus 6 fixed bits that mark the version (4) and variant. It is written as 32 hexadecimal digits in the pattern 8-4-4-4-12, for example 3f2b8c1e-7a4d-4f6b-9c2e-1d5a8b7e6f40. The third group always starts with 4.
Random values come from crypto.randomUUID or crypto.getRandomValues.
Examples
- Standard:
9b1deb4d-3b7d-4bad-9bdd-2b0d7b3dcb6d - No hyphens, uppercase:
9B1DEB4D3B7D4BAD9BDD2B0D7B3DCB6D
Frequently asked questions
Can two UUIDs ever be the same?
In theory yes, but with 122 random bits the chance is so small that you would need to generate billions per second for many years to expect a single duplicate.
Is a GUID the same as a UUID?
Yes. GUID is Microsoft’s name for the same 128-bit identifier format.