UUID generator

UUID generator is a free tool that runs entirely in your browser, with no data ever sent to a server. Version 4 unique identifiers, one at a time or by the hundreds.

What a UUID is for

A UUID (universally unique identifier) names a database row, a session, a file or a resource without coordinating a central counter : the odds of two generators producing the same identifier, anywhere, are so low they're treated as zero in practice.

Why "version 4"

There are several ways to build a UUID : from the time, from a network address, or fully at random. Version 4, the most common today, draws every bit randomly, except for a handful of fixed bits that mark it as a version 4 UUID.

What this tool does not do

This tool only performs the calculation described above, without checking how you intend to use the result. There is no limit set by the tool itself : the only constraint is your device's memory.

Frequently asked questions

Could two UUIDs generated here be identical?

In theory yes, in practice no : you would need to generate billions of UUIDs per second for decades to have a reasonable chance of a single collision.

Is the generated batch sent anywhere to check for duplicates?

No, everything stays on the page. It isn't even necessary, given how unlikely a collision is.

Do I need to create an account or install anything?

No : the tool works directly on this page, with no sign-up and no install.