UUID / GUID Generator

About this calculator

This tool generates one or more random UUIDs (Universally Unique Identifiers), specifically version 4, which is built almost entirely from random bits formatted into the standard 36-character pattern like xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx. The chance of two version-4 UUIDs ever colliding is astronomically small, which is what makes them usable as unique identifiers without needing a central authority to hand them out or check for duplicates.

It is used by software developers assigning unique IDs to database rows, API resources, session tokens, or file names where a simple incrementing number either isn't available or would leak information (like how many records exist). QA engineers and testers also generate them on the fly to create realistic-looking unique test data without having to invent IDs by hand.