UUID Generator
Generate random version 4 UUIDs (GUIDs) in bulk — lowercase, uppercase, with or without hyphens.
UUIDs are generated in your browser with the Web Crypto API and are never sent to a server.
About this tool
Create up to 500 random UUIDs at once for database keys, test data or config files. Each one is a standard version 4 UUID with 122 random bits, generated in your browser with the Web Crypto API. Choose upper or lower case, hyphens, no hyphens or braces.
Frequently asked questions
A UUID (universally unique identifier) is a 128-bit ID written as 32 hexadecimal digits in five groups, 8-4-4-4-12, e.g. 3f2b8c1e-9a4d-4f6b-8e21-7c5d0a9b1f34. Microsoft calls the same format a GUID.
A v4 UUID is made from random numbers. Six bits are fixed to mark the version and variant, so the third group always starts with 4 and the fourth group starts with 8, 9, a or b; the other 122 bits are random.
In practice no. With 122 random bits there are about 5.3 × 10³⁶ possible values, so you would need to generate billions of UUIDs per second for many years before a duplicate became likely.
Yes. They are created in your browser with the cryptographically secure Web Crypto API and are never sent to or stored on a server.