A version-7 UUID begins with a 48-bit Unix millisecond timestamp followed by random bits, standardised in RFC 9562. Because the time comes first, v7 UUIDs sort in creation order while keeping the global uniqueness of a UUID.

Why use v7 over v4 for database keys?

Random v4 UUIDs scatter writes across an index and fragment B-trees. The time-ordered prefix of v7 keeps inserts roughly sequential, which improves index locality and write performance.

Is anything uploaded?

No. The timestamp and random bits are generated in your browser with Web Crypto and nothing is uploaded.

UUID v7 Generator — Gera Tools

Sortable UUID v7 generator

A UUID v7 leads with a 48-bit Unix millisecond timestamp and fills the rest with cryptographic randomness, as standardised in RFC 9562. The result is a UUID that sorts in creation order — combining the time-ordering of an auto-increment key with the decentralised uniqueness of a UUID.

That ordering makes v7 the modern default for database primary keys: inserts stay roughly sequential, so indexes don’t fragment the way random v4 keys cause them to. This tool generates one ID or a sortable batch, all in your browser, nothing uploaded.