Generators

UUID Generator

Generate various versions of UUID/GUID.

Generated UUIDs0 items
Click "Generate" to create UUIDs

What is a UUID Generator?

UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify information. UUIDs are designed to be globally unique without requiring a central authority.

UUID Versions

  • UUID v4 (Random): Generated using random numbers, most commonly used
  • UUID v1 (Time-based): Based on timestamp and MAC address
  • NanoID: Shorter, URL-friendly unique IDs

Use Cases

  • Database Primary Keys: Unique record identifiers
  • Session IDs: User session management
  • File Names: Unique file identifiers
  • API Tokens: Request tracking and authentication

Frequently Asked Questions

How unique is a randomly generated UUID (v4)?
A v4 UUID carries 122 random bits. After generating on the order of 2^61 UUIDs, the chance of any collision is still around one in a billion — for practical purposes, generated IDs never collide.
Which UUID version should I use?
Use v4 for general-purpose IDs. If IDs serve as database primary keys or need time-ordered indexes, prefer v7: random v4 keys fragment B-tree indexes under heavy insert load.
Can I shorten a UUID for use in URLs?
Yes. Convert it to its 16 raw bytes and encode as Base64URL: 36 characters shrink to 22. Keep it URL-safe; decoding the Base64URL back to bytes restores the original UUID.