UUID v7 Generator
Time-sortable UUIDs that sort by creation order — the modern default for database primary keys.
Why UUID v7?
UUID v7 is a 2024 addition to the spec (RFC 9562) designed specifically to fix the database-index pain points of v4. The first 48 bits encode a Unix millisecond timestamp; the remaining 74 bits are random. Because the timestamp is the high-order bits, v7 IDs sort chronologically by creation time — which means new rows insert at the end of a B-tree primary-key index instead of randomly throughout it. The result is dramatically better INSERT throughput and reduced index fragmentation versus v4. v7 is rapidly becoming the recommended default for new applications choosing UUIDs as primary keys. Encoded right in your browser via crypto.getRandomValues().
Generated UUIDv7
Generating...
Format
Bulk Generation
Count:
UUID Validator
Recent UUIDs
Generated UUIDs will appear here.
Last 20 UUIDs are kept in history.
Last 20 UUIDs are kept in history.
About UUID v7 (RFC 9562)
RFC 9562 (May 2024) defines UUID v6/v7/v8; v7 is the unix-ms timestamp + random variant.
- Layout: 48-bit unix-ms timestamp | 4-bit version (7) | 12-bit random | 2-bit variant | 62-bit random
- Format: xxxxxxxx-xxxx-7xxx-yxxx-xxxxxxxxxxxx
- First 48 bits = Date.now() milliseconds, big-endian
- Lexicographic sort = chronological sort (millisecond precision)
- 74 bits of entropy from crypto.getRandomValues()