UUID Generator

A UUID is a number that is practically guaranteed to exist only once - the universal way to give a record, a file or an event a unique identifier without needing a central authority. This generator produces exactly those IDs, and not just one kind but the whole family.

UUID v4 is the standard: purely random, ideal for most cases. UUID v1 is based on time and node, UUID v7 combines a timestamp with randomness and is therefore naturally sortable - perfect as a database key, because records that are close in time also sit close together in the index. On top of that come ULID and Nano ID, two more modern, compact alternatives, with Nano ID even offering a custom length and character set.

The output format adapts. Standard with hyphens, all upper case, without hyphens, in braces for certain Microsoft contexts or as a URN with the urn:uuid prefix. So you get the ID in exactly the notation your code or database expects.

If you need many IDs, generate them in batch - a whole list at once, ready to copy. A validation mode goes the other way: paste an existing UUID and the tool tells you whether it is valid, which version and variant it has and, for v1 and v7, what timestamp it contains.

A local history remembers what you generated last, so you can find an ID again later. Everything is stored only in your browser, nothing travels outside.

The IDs are created cryptographically at random via the Web Crypto API and entirely locally. No server contact, no transmission, no signup. The tool is fast, works offline and is therefore suitable even for sensitive environments where no data may leave the device.