UUID Generator
Generate random version 4 UUIDs using your browser's secure random source, one or fifty at a time. Free and private.
Random version 4 UUIDs, on tap
A UUID is a 128-bit identifier unique enough that you can mint one anywhere without checking a central list, which is why they show up as database keys, request IDs, and file names. This UUID generator uses your browser's built-in secure random source to produce standard version 4 UUIDs, one at a time or fifty at once. Copy a single line or grab the whole batch. Nothing is generated on a server, so the values are yours alone.
Find the ID you used yesterday
The hard part is rarely making an ID. It is finding the one you already used. Relic keeps an end-to-end encrypted, searchable history of everything you copy, on every device, so the UUID you pasted into a test yesterday is one search away today. Generating them is free. Never losing track of them is what Relic is for.
Learn: new to UUIDs, or wondering when to use v4 vs v7? Read What is a UUID?
Frequently asked questions
What is a UUID?
A UUID (universally unique identifier) is a 128-bit value, usually written as 32 hexadecimal digits in five dash-separated groups. It is unique enough that you can mint one anywhere without checking a central registry, which is why UUIDs are used for database keys, request IDs, and file names.
Which UUID version does this generate?
Version 4, the random kind. It uses your browser's built-in secure random source (crypto.randomUUID), so 122 of the 128 bits are random and the rest are fixed version and variant markers. Generate one at a time or up to fifty at once.
Can two version 4 UUIDs ever collide?
In theory yes, because they are random rather than coordinated, but in practice the odds are astronomically small. You would need to generate billions of UUIDs before a collision became remotely likely, so for real applications they are treated as unique.
What is the difference between UUID v4 and v7?
Version 4 is fully random, so values land all over the place. Version 7 embeds a timestamp, so IDs sort roughly in creation order, which is friendlier to database indexes. This tool generates v4, which is the right default unless you specifically want time-ordered keys.
Are these UUIDs generated privately?
Yes. They are created by your browser's random source, not on a server, so the values are yours alone and nothing is transmitted.