01 / encoding —UUID Generator

LIVE

Version

Namespace (v5 only)

Count

Output format

UPPERCASE hyphens {braces}

Output

What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify information in computer systems.

Versions

v1 — time-based. Includes timestamp and MAC address.
v4 — random. Most common. 122 bits of randomness.
v5 — name-based (SHA-1 hash). Deterministic.
v7 — time-ordered, sortable, random. New RFC 9562 standard.

When to use which

Use v4 for most cases. Use v7 when you need database-friendly ordering. Use v5 when you need deterministic IDs from a name.