UUID generator
Create unique IDs in the standard UUID (GUID) format, one at a time or in bulk. They are made in your browser from secure random numbers.
Entirely random. The usual choice when you just need a unique ID.
Check a UUID
What is a UUID?
A universally unique identifier: a 128-bit number written as 32 hexadecimal digits. Anyone can create one without asking a central registry, and the chance of two ever matching is negligible. Microsoft calls the same thing a GUID.
Version 4 or version 7?
- Version 4
- 122 random bits. Reveals nothing about when or where it was made. The safe default.
- Version 7
- The first 48 bits are the time in milliseconds, the rest are random. New IDs sort after old ones, which keeps database indexes compact. Anyone who sees the ID can read when it was created.
Can two UUIDs collide?
In theory, yes; in practice, no. You would need to generate about a billion version 4 UUIDs every second for about 86 years to reach an even chance of one repeat.
Are UUIDs secret?
They are unique, not secret. Do not use a UUID on its own as a password or an access token; use the password generator for secrets.
Is anything uploaded?
No. IDs are generated in your browser and this page loads no ads.
Related tools
Read the time inside a version 7 ID with the timestamp converter, or browse all utilities.