UUID/GUID Generator
Version
UUIDs (Universally Unique Identifiers) are 128-bit values used to identify records, sessions, and resources without a central authority handing out IDs. This generator produces version 4 (random) or version 1 (time-based) UUIDs, individually or in bulk up to 1000 at a time, with options for case and hyphenation. All generation happens locally using your browser's cryptographically secure random number generator.
Frequently asked questions
What's the difference between v1 and v4 UUIDs?
A v4 UUID is almost entirely random, making it unpredictable and ideal for most use cases. A v1 UUID encodes a timestamp plus a node identifier, which makes UUIDs sortable by creation time but can leak generation time — this tool uses a random node ID rather than a real MAC address for privacy.
Are these UUIDs guaranteed to be unique?
V4 UUIDs have 122 random bits, making collisions astronomically unlikely even across billions of IDs. They're generated using the Web Crypto API's cryptographically secure random values.
Can I generate UUIDs without hyphens or in uppercase?
Yes — toggle 'Hyphens' to get a continuous 32-character hex string, and toggle 'Uppercase' to change the letter casing. Both are common requirements for specific databases or APIs.