UUID generator

Generate UUID v4 values in your browser with the Web Crypto RNG. Nothing is uploaded.

Generate UUID version 4 values in this tab.

How to use the UUID generator

Set how many IDs you need (up to 1,000).
Click Generate. Hyphens are on; uppercase is optional.
Copy the list into a fixture, database seed, or request id header.

Version 4

Each ID is 122 bits of randomness with the v4 version and variant bits set. This is not a v1 time UUID and not a ULID. Refreshing the page does not keep old values unless you copied them.

Nothing is uploaded

crypto.randomUUID or getRandomValues in this tab.

UUID generator FAQ

Are they unique?

Collisions are negligible for ordinary lab use. Do not treat them as secret tokens by themselves.

No hyphens?

Uncheck Hyphens for a 32-character hex string.

Sorted list?

Generate, copy, then use the line sorter if you need order.