UUID Generator
Generate single or bulk UUID v4 identifiers locally.
UUID generator online
This UUID generator creates universally unique identifiers (version 4, random) instantly and in your browser. They work as database keys, object identifiers or tokens wherever you need a value that won’t repeat.
What a UUID is
A UUID (Universally Unique Identifier) is a 128-bit number shown as 32 hexadecimal digits in the 8-4-4-4-12 format, for example 3f2a1c4e-9b7d-4f6a-8e21-0c5d9a1b2c3d. UUID v4 is almost entirely random.
Why are they unique?
A v4 UUID has so many possible combinations (2 to the power of 122) that the chance of generating two identical ones is negligible in practice, even across millions. That’s why different systems can generate them without coordinating and still not collide.
What they’re used for
- Primary keys in distributed databases.
- Identifying files, events or requests.
- Idempotency: avoiding processing the same operation twice.
Frequently asked questions
Can two UUIDs repeat? In theory yes, but the probability is so low it’s treated as zero in practice.
Which version does it generate? UUID v4 (random), the most common for general identifiers.
Is it secret or secure? It’s unique, not secret; don’t use it as a password or security token on its own.