UUID Generator
Generate random version-4 UUIDs / GUIDs in bulk.
About the UUID Generator
UUIDs (also called GUIDs) are 128-bit identifiers used as primary keys, request IDs and unique references across databases and APIs. The AlarmDaddy UUID Generator creates random version-4 UUIDs instantly — one or a hundred at a time — each with a one-click copy.
It uses the browser's native crypto.randomUUID where available, so the identifiers are standards-compliant and cryptographically random. Everything runs locally.
How to use this calculator
- 1Set how many UUIDs you need.
- 2Click Generate.
- 3Copy a single UUID, or copy them all at once.
The formula
A v4 UUID is mostly random: 122 bits come from a secure random source, while a few bits are fixed to mark it as version 4, variant 1. The result is formatted as 8-4-4-4-12 hexadecimal digits. Collisions are astronomically unlikely.
Frequently asked questions
A v4 UUID is generated almost entirely from random data (per RFC 4122). It is the most common UUID type for database keys and API identifiers because it needs no central coordination.