UUID Generator
Create unique IDs for database rows, test data or API requests. Pick version 4 for fully random IDs or version 7 for IDs that sort by creation time, and generate one or a thousand at a time.
How to generate UUIDs
- 1Choose version 4 or version 7.
- 2Set how many you need and the format.
- 3Copy one, copy all, or download them as a text file.
Version 4 or version 7
Version 4 UUIDs are 122 random bits, the most common choice. Version 7 (RFC 9562) starts with the creation time in milliseconds, so new IDs sort after old ones. That keeps database indexes compact and makes IDs roughly chronological.
Secure randomness
IDs come from your browser's cryptographically secure random generator, the same one used for encryption keys, so they're unpredictable and practically never repeat.
Formats
The standard form is 36 characters with hyphens, like 3f6c2a9e-8b1d-4e7a-9c3f-2d5b8a1e6f40. Some systems store UUIDs without hyphens or in uppercase; both options are there.
Frequently asked questions
- Can two UUIDs ever be the same?
- In theory, but the chance is so small it's ignored in practice: you'd need to generate billions per second for many years.
- Is a GUID the same as a UUID?
- Yes. GUID is Microsoft's name for the same 128-bit identifier.
- Are generated UUIDs stored?
- No. They're created in your browser and never sent or saved.