UUID Generator

How to generate UUIDs

1. Enter how many UUIDs you need (1 to 100).
2. Optionally tick Uppercase or Remove hyphens to match your required format.
3. Click Generate, then Copy all to grab them — one per line.

What is a version 4 UUID?

A UUID (universally unique identifier, also called a GUID) is a 128-bit value written as 36 characters, for example 550e8400-e29b-41d4-a716-446655440000. Version 4 UUIDs are built from random data: 122 of the 128 bits are random, while the remaining bits mark the version (the 4 in the third group) and the variant. Because they are random, you can generate them anywhere — on any machine, with no central registry — and still treat them as unique. They are used everywhere: database primary keys, API request IDs, file names, session tokens and distributed systems.

Will two UUIDs ever collide?

Practically, no. With 122 random bits there are about 5.3 × 10³⁶ possible v4 UUIDs. You would need to generate roughly a billion UUIDs every second for about 85 years before the odds of a single duplicate reached 50%. For any normal application, v4 UUIDs can be treated as globally unique. This tool uses your browser's cryptographically secure random generator, not a predictable one, so the randomness is high quality.

Is it private and safe?

Yes. Every UUID is generated with the Web Crypto secure random generator, entirely on your device. Nothing is ever uploaded, stored or transmitted — the page works even offline once loaded.