A UUID—Universally Unique Identifier—is a 128-bit value usually shown as 36 characters with hyphens, like 550e8400-e29b-41d4-a716-446655440000. The idea is that it’s practically unique across systems and time. You can generate one on your machine without checking a database or asking a central server. So UUIDs get used for primary keys in databases, request IDs in logs, file names, and anywhere you need a unique ID without a single authority handing them out. Collisions are so unlikely that in normal use you can treat them as impossible.
When do you use a UUID generator? When you’re prototyping and need a quick unique ID for a new record or entity. When you’re writing tests and need IDs that don’t clash. When you’re building an API and want to generate correlation IDs or resource IDs. When you’re replacing placeholder IDs in configs or scripts. Your app or database might generate UUIDs too—but sometimes you need one right now without opening code or a DB client. A generator gives you one (or several) at the click of a button. Copy, paste, done.
Most generators produce version 4 UUIDs—random. Each new one is statistically unique. You don’t have to worry about two systems generating the same ID. That’s why they’re so handy for distributed systems, offline-first apps, and anything where you can’t rely on a single counter or sequence.
Our UUID generator is free and runs in your browser. Click to generate one or more UUIDs. Copy the one you need. No sign-up, no data sent anywhere—generation happens locally. Use it whenever you need a unique ID in a hurry.