UUID Generator
Generate cryptographically random v4 UUIDs, one at a time or in bulk.
Options
Result
Bulk-generate version 4 UUIDs
A UUID (universally unique identifier) is a 128-bit value used to identify records, sessions, or objects without a central authority handing out IDs. Version 4 UUIDs are generated from random bits, making collisions astronomically unlikely — this tool generates them using your browser's cryptographically secure random number generator.
Also useful: Password Generator and JSON Formatter & Validator.
Frequently asked questions
A version 4 UUID has 122 random bits, giving roughly 5.3×10^36 possible values. You'd need to generate billions of UUIDs per second for billions of years before a collision became likely.
Yes — toggle either option before generating. Both are common formats some systems and APIs expect instead of the standard lowercase, hyphenated form.
Yes — this uses the Web Crypto API's crypto.getRandomValues, the same cryptographically secure source browsers use for security-sensitive randomness, entirely on your device.