UUID Generator

The UUID Generator creates universally unique identifiers (UUIDs): random 128-bit values written as 36 characters in the familiar 8-4-4-4-12 pattern, for example 7f8025fb-3c7e-4d90-ae56-b55629112d57. UUIDs are used as database keys, session and order identifiers, file names, and test-data values — anywhere you need an identifier that is practically unique without a central counter.

This tool generates version 4 (random) UUIDs. The version digit appears in the third group: in the example above it is the 4 in 4d90.

How to Use the UUID Generator

1. Open the UUID Generator page in your browser.
2. Enter how many UUIDs you want in the Number of UUIDs field (the default is 1).
3. Tick Uppercase if you want uppercase letters instead of the default lowercase.
4. Click Process.
5. Copy the UUIDs from the result panel.

Worked Example

With Number of UUIDs set to 3 and Uppercase off, this page generated three UUIDs in one run. The first two were:

7f8025fb-3c7e-4d90-ae56-b55629112d57
24c6cfad-92f1-440b-a571-caa9c117a34b

Each is 36 characters long including four hyphens, and each has 4 as the first character of the third group, marking it as a version 4 UUID. Running the generator again produces a completely different set.

Limitations

• The generated UUIDs appear space-separated on a single line in the result panel, not one per line, so paste them into a text editor and split them if your workflow needs one UUID per line.
• Only version 4 (random) UUIDs are generated. There is no control to choose version 1 (time-based), version 7 (time-ordered), or namespace-based version 5 UUIDs.
• There is no validation or decoding control: the tool generates UUIDs but does not check or parse a UUID you paste in.
• UUIDs are unique in practice, not by guarantee. Collisions are astronomically unlikely but not mathematically impossible, and randomness depends on the browser’s random-number source.

Frequently Asked Questions

Which UUID version does this tool generate?

Version 4 (random). You can confirm it from the version digit: the first character of the third group is 4.

Are generated UUIDs guaranteed to be unique?

No, but collisions are so unlikely that UUIDs are treated as unique for practical purposes. With 122 random bits, the chance of two generated UUIDs matching is negligible.

Can I generate uppercase UUIDs?

Yes. Tick the Uppercase checkbox before clicking Process and the letters A–F will be uppercase.

Can I generate many UUIDs at once?

Yes. Enter the number you need in the Number of UUIDs field and click Process to generate the whole batch in one run.