uuidv7

An experimental implementation of the proposed UUID Version 7

import { uuidv7 } from "uuidv7";

const result = uuidv7(); // e.g. "017fe250-610a-77d7-aca2-324d29c92b45"

See draft-peabody-dispatch-new-uuid-format-03.

Field and bit layout

This implementation produces identifiers with the following bit layout:

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                          unix_ts_ms                           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|          unix_ts_ms           |  ver  |        counter        |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|var|                        counter                            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                             rand                              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Where:

• The 48-bit unix_ts_ms field is dedicated to the Unix timestamp in milliseconds.
• The 4-bit ver field is set at 0111.
• The 42-bit counter field accommodates the sequence counter that ensures the monotonic order of IDs generated within the same millisecond. The counter is incremented by one for each new ID generated within the same timestamp and is randomly initialized whenever the timestamp changes.
• The 2-bit var field is set at 10.
• The remaining 32 rand bits are filled with a cryptographically strong random number.

License

Licensed under the Apache License, Version 2.0.