UUID Generator
Generate random UUID v4 identifiers.
Generated UUID
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit identifier that is practically unique across all systems. The format is 8-4-4-4-12 hexadecimal digits, like 550e8400-e29b-41d4-a716-446655440000. UUIDs are designed to be generated independently without coordination between systems.
UUID Versions
- Version 1 uses timestamp and MAC address, which can reveal when and where it was created
- Version 4 uses random numbers, making it the most common choice for general use
- Version 5 uses SHA-1 hashing of a namespace and name for deterministic generation
Common Uses for UUIDs
- Primary keys in databases without auto-increment coordination
- Session identifiers and authentication tokens
- Unique file names and temporary identifiers
- Distributed systems where multiple nodes need to generate unique IDs