UUID generator
Generate random version 4 UUIDs, one or many, in your browser.
This UUID generator produces universally unique identifiers you can drop into databases, API requests, and distributed systems without coordinating with a central authority. It creates version 4 UUIDs, which are built from random values and offer such an enormous range of possible outputs that collisions are effectively impossible in practice. Generate a single identifier or a whole batch at once, then copy the results in the format you need. Generation runs locally using your browser's secure random source, so no values are sent over the network.
Frequently asked questions
What is a version 4 UUID?
It is a 128-bit identifier generated mostly from random data, formatted as 32 hex digits in five hyphen-separated groups.
Could two generated UUIDs ever collide?
The odds are vanishingly small. You would need to generate billions before a collision became remotely likely.
Can I generate many at once?
Yes. You can produce them in bulk and copy the entire list, with no limit on how many you create.
What's the difference between UUID v4 and v7?
v4 is fully random, while the newer v7 embeds a timestamp so identifiers sort roughly in creation order — which is friendlier for database index performance. This tool generates v4, the most universally supported version.
Are UUIDs case-sensitive?
No. The hex digits are conventionally lowercase but are equivalent in uppercase, so 1A2B and 1a2b represent the same value. Pick one case and stay consistent in your data.
Can I use a UUID as a database primary key?
Yes, and it's common for distributed systems since IDs don't need a central counter. Be aware that random v4 keys can fragment B-tree indexes, which is why time-ordered variants exist.
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