Use for identifiers, tests, and prototypes. Each value is a random 128-bit UUID in standard string form.
UUID
How it works
The browser generates a random UUID v4 and displays it.
Format is eight, four, four, four, and twelve hexadecimal digits per group with fixed version and variant bits per RFC 4122.
What is a UUID?
A UUID is a 128-bit identifier. Version 4 uses random bits (except required version/variant fields).
Uniqueness
Collisions are astronomically unlikely for random v4 UUIDs; still use database constraints if uniqueness is critical.
Common questions
- Are these UUIDs truly unique?
- Random v4 UUIDs are practically unique; not guaranteed by the spec, but collision risk is negligible at typical scale.
- UUID v1 vs v4?
- v1 embeds time and MAC-derived data; v4 is random. This tool only generates v4.
- Can I use these as database keys?
- Often yes; consider index size and sequential vs random insert patterns for your engine.
- Offline?
- Yes. No network is required.