UUID Generator

What is UUID?

UUID (Universally Unique Identifier) is a 128-bit identifier standard used to uniquely identify information in software systems. It was originally defined by RFC 4122, which has been superseded by RFC 9562.

UUIDs are widely used for database primary keys, distributed system identifiers, API request tracing and log correlation.

Standard UUID Format

The standard string representation of a UUID is:

xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

It contains 32 hexadecimal characters and 4 hyphens. Example: 550e8400-e29b-41d4-a716-446655440000.

UUID Versions

• Version 1 (v1): Based on timestamps and node information. It provides time-related ordering but may expose node information.
• Version 3 (v3): Uses MD5 hashing with a namespace UUID and name. The same input produces the same UUID.
• Version 4 (v4): Generated from random data and is one of the most commonly used UUID versions.
• Version 5 (v5): Uses SHA-1 hashing with a namespace UUID and name. It is deterministic like v3.
• Version 6 (v6): Reorders timestamp information from v1 to provide more natural sorting.
• Version 7 (v7): Uses a Unix millisecond timestamp and is designed to provide time-ordered UUIDs. It is recommended for many new systems that need sortable UUIDs.

Choose a UUID version according to your requirements for ordering, determinism, compatibility and randomness.

UUID Generator Features

• Generate UUIDs in multiple supported versions.
• Generate multiple UUIDs at once.
• Copy generated UUIDs quickly.
• Parse and validate UUID values.
• Use UUIDs for development, testing, databases, APIs and distributed systems.