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UUID Generator v1
Generate a real RFC 4122 version 1 (time-based) UUID, encoding the current timestamp plus a randomly-generated node identifier.
How to Use UUID Generator v1
- 1Click Process to generate a new time-based UUID v1
- 2Copy the result
- 3Click Process again for another one (timestamp and node will differ)
Frequently Asked Questions
A 60-bit timestamp (100-nanosecond intervals since October 15, 1582) split across the time_low/time_mid/time_hi fields, a random clock sequence, and a 48-bit node identifier — with the version nibble set to 1 and the RFC 4122 variant bits set correctly.
No — it uses cryptographically random bytes with the multicast bit set, the RFC 4122-recommended approach when a real IEEE 802 address isn't used, specifically to avoid leaking a real hardware identifier.
Roughly, yes — unlike random v4 UUIDs, v1 UUIDs are approximately chronologically ordered, though not as cleanly sortable as a purpose-built format like ULID (also on this site) since the timestamp bits aren't in strict most-significant-first byte order.
No — generation happens entirely in your browser using the Web Crypto API for the random components.
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