UUID Generator
Generate RFC 4122 v4 UUIDs, single or in bulk.
Single UUID
UUID v4
40ea3407-057a-42d0-9b37-14a711085ff7
Bulk Generate
Examples
| Input | Result |
|---|---|
| Generate single UUID | f47ac10b-58cc-4372-a567-0e02b2c3d479 |
| Generate single UUID | 9b1deb4d-3b7d-4bad-9bdd-2b0d7b3dcb6d |
| Bulk generate 5 UUIDs | 1b9d6bcd-bbfd-4b2d-9b5d-ab8dfbbd4bed 6ec0bd7f-11c0-43da-975e-2a8ad9ebae0b 3fa85f64-5717-4562-b3fc-2c963f66afa6 7c9e6679-7425-40de-944b-e07fc1f90ae7 e4eaaaf2-d142-11e1-b3e4-080027620cee |
| Bulk generate 3 UUIDs | a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11 2c5ea4c0-4067-11e9-8bad-9b1deb4d3b7d d9428888-122b-11e1-b85c-61cd3cbed5f3 |
About this tool
This tool generates version 4 UUIDs that conform to RFC 4122. Each UUID is produced using cryptographically secure random values from your browser, so they are suitable for use as database keys, API identifiers, or any situation where you need globally unique IDs without a central registry.
You can generate a single UUID with one click or produce up to 1,000 at once using the bulk generator. The bulk output is newline-separated plain text, ready to copy and paste into a migration script, seed file, or test fixture. Everything runs client-side with no network requests involved.
Frequently asked questions
What is a v4 UUID and when should I use one?
A v4 UUID is a 128-bit identifier generated from random or pseudo-random numbers, following RFC 4122. They are commonly used as database primary keys, session tokens, and anywhere you need a unique ID without coordinating with a central authority.
Can two v4 UUIDs ever collide?
Theoretically yes, but the probability is astronomically low. With 122 random bits, you would need to generate about 2.71 quintillion UUIDs to have a 50% chance of a single collision. In practice, it does not happen.
What is the format of a UUID?
A UUID is 32 hexadecimal digits displayed in five groups separated by hyphens: 8-4-4-4-12. For v4 UUIDs, the 13th character is always "4" and the 17th character is one of "8", "9", "a", or "b".