Generate random version 4 UUIDs (also called GUIDs) in one click. Choose how many you need, and whether you want uppercase or no hyphens, then copy them.
How it works
A version 4 UUID is a 128-bit number made from random data. The generator fills 16 random bytes using your browser’s secure random source, sets the version digit to 4 and the variant bits as the standard requires, then writes the bytes in the familiar 8-4-4-4-12 pattern.
The chance of two random UUIDs colliding is extremely small, which is why they are used as identifiers in databases and software.
Example
A UUID looks like 3f2b8c1e-7a4d-4e6b-9c2a-5d1f0e8b7a63. The 4 at the start of the third group marks version 4.
Frequently asked questions
Are these UUIDs unique?
They are random, so collisions are astronomically unlikely, though not strictly impossible.
What is the difference between a UUID and a GUID?
GUID is Microsoft’s name for the same kind of identifier.
Are they secure enough for secrets?
They are random, but do not use a UUID as a password or token without checking your security requirements.
More free tools: Password generator · Random number generator · All free tools
Everything runs in your browser. Nothing you enter is sent or stored.