Runs locally in your browser
UUID Generator
Generate secure random UUID v4 or time-sortable UUID v7 values in bulk. Format and download the results without sending data anywhere.
UUID v4 vs. UUID v7
UUID v4 uses random data and is widely supported. UUID v7 combines a Unix millisecond timestamp with random bits, so newly generated identifiers sort roughly by creation time and can improve database index locality.
| Version | Choose it when | Property |
|---|---|---|
| UUID v4 | Compatibility and opaque random identifiers are the priority | Random; generation order is not visible |
| UUID v7 | New records benefit from chronological sorting | Time-ordered with random data after the timestamp |
UUID format
A standard UUID contains 128 bits and is normally displayed as 32 hexadecimal characters separated into five groups. Uppercase and removing hyphens only change presentation, not the underlying identifier.
Export UUIDs for code or data
Generate one value for a record ID or create a batch for fixtures, imports, and test data. Plain text places one UUID on each line, JSON creates a string array, and CSV creates a single-column table. Case and hyphen settings change formatting only; use the representation expected by the destination system.
A UUID is an identifier, not a secret, access token, or encryption key. Even a securely generated random UUID should not replace authentication or authorization checks.
Frequently asked questions
What is the difference between UUID v4 and UUID v7?
UUID v4 is random. UUID v7 includes a millisecond timestamp followed by random data, which makes values naturally sortable by creation time.
Are these UUIDs generated securely?
Yes. The generator uses the browser Web Crypto API and its cryptographically secure random source.
Can two generated UUIDs be the same?
A collision is theoretically possible, but the probability is extraordinarily small when UUIDs are generated with a secure random source.