What a UUID is
A UUID is a long, practically unique identifier, like
f47ac10b-58cc-4372-a567-0e02b2c3d479. Databases, APIs and logs use them to label
records without collisions.
Why version 4
Version 4 UUIDs are random, generated from a secure random source in your browser. That makes them ideal when you need an ID that cannot be guessed.
- Primary keys in a database
- Request and trace IDs in logs
- File and session names
Frequently asked questions
Are these UUIDs really unique?
A version 4 UUID has about 122 random bits, so the chance of a duplicate is vanishingly small.
Are they generated securely?
Yes, they use the browser's cryptographically secure random generator.
How many can I make at once?
Up to 100 in a single batch.