UUID Generator
Bulk v4 UUIDs with format options and one-click copy
How to Use
UUIDs (universally unique identifiers) are widely used for database primary keys, distributed system IDs and temporary file names. This tool generates RFC 4122 compliant v4 UUIDs using your browser's crypto-grade random number generator (crypto.getRandomValues), making collisions practically impossible.
How to use: choose how many UUIDs to generate (1-100) and the format (upper/lowercase, with or without hyphens), then click "Generate". Copy them one by one or all at once. Everything is generated locally, offline.
FAQ
Could two generated UUIDs collide?
A v4 UUID has 122 random bits — the collision probability is astronomically small (on the order of 1 in 10^36), so for practical purposes they are unique.
What's the difference between v4 and v1 UUIDs?
v1 is derived from a timestamp and MAC address, which can leak device information. v4 is purely random, carries no device or time data, and is the most widely used version today.
Does generation require a network connection?
No. UUIDs are produced by your browser's local random generator and never go through any server.