UUID

A free online UUID generator that creates version 4 (random) and version 7 (time-ordered) UUIDs in bulk, right in your browser. Generate a single identifier or a batch of up to 100, and format the output to match your needs — uppercase, wrapped in braces, or with the hyphens removed. Reach for v4 when you just need a unique random id, and v7 when you want identifiers that sort by creation time, which improves index locality when they are used as database primary keys. Generation is local, so the identifiers are yours alone.

Common uses

• Generate a batch of v4 UUIDs for test fixtures or seed data.
• Create time-ordered v7 UUIDs that sort naturally by creation time as database keys.
• Produce a hyphen-free or brace-wrapped UUID to match a specific format requirement.
• Grab a single unique id quickly while writing code or a migration.
• Generate uppercase UUIDs to match an existing system’s convention.

Frequently asked questions

What is the difference between UUID v4 and v7?

v4 is fully random. v7 embeds a Unix timestamp so the values are time-ordered, which improves locality when used as database primary keys.

How many UUIDs can I generate at once?

You can generate between 1 and 100 UUIDs in a single batch.

Are these UUIDs unique enough to rely on?

Yes. v4 draws 122 random bits, making collisions astronomically unlikely, and v7 combines a timestamp with random bits, so both are safe as unique identifiers in practice.

Why would I use v7 instead of v4 as a database key?

Because v7 values are time-ordered, new rows insert near each other in the index rather than scattering randomly, which reduces index fragmentation and can improve write performance.

Are the generated UUIDs sent to a server?

No. They are generated locally in your browser, so the values are never transmitted.