Generate cryptographically random version-4 UUIDs for database keys, API identifiers, and test data. Make one or hundreds, with optional uppercase, and export the set.
UUIDs (also called GUIDs) are the standard way to give something a globally unique identifier without a central authority handing out numbers. Developers use them for primary keys, API request IDs, file names, and idempotency tokens. This tool generates version 4, which is almost entirely random.
Generate them in bulk and export as a text list, a CSV column, or a JSON array to drop straight into code or a database seed. The variant and version bits are set correctly, so every value is a valid RFC-style v4 UUID.
Frequently asked questions
What is a v4 UUID?
A 128-bit identifier that is almost entirely random, formatted as 8-4-4-4-12 hexadecimal digits. Collisions are astronomically unlikely.
Are these safe to use as IDs?
Yes — they're generated with your device's cryptographic random source, so they're suitable for production identifiers.
Uppercase or lowercase?
Lowercase is the common convention, but some systems expect uppercase; toggle the option to match yours.
How unlikely is a collision?
With 122 random bits, you could generate billions of UUIDs and still have a negligible chance of any two matching.