UUID Generator
Generate random v4 and time-ordered v7 UUIDs in bulk, using your browser's secure random source.
🔒 Generated locally with the Web Crypto API. Nothing is sent to a server.
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About UUIDs
A UUID (Universally Unique Identifier) is a 128-bit value usually written as 32 hexadecimal digits in the form 8-4-4-4-12. They let independent systems generate identifiers without coordinating, with a vanishingly small chance of collision.
v4 is fully random and is the most common choice. v7 (from the updated UUID spec) places a millisecond Unix timestamp in the high bits, so freshly generated values sort chronologically — this gives databases much better index locality than random v4 keys, which is why v7 is increasingly used for primary keys.
FAQ
- Are these cryptographically random?
- Yes — they use the browser's
cryptosecure random source, generated entirely on your device. - v4 vs v7?
- v4 is fully random; v7 is time-ordered (sortable by creation time), which is better for database keys.
- Are UUIDs guaranteed unique?
- Not strictly, but collisions among random UUIDs are so improbable they're safely ignored in practice.