UUIDv7 solves a real database problem. It also quietly invites a bad assumption: that the ID tells you the time, and that time is a safe thing to show the world.

A post from October 19, 2026, "UUIDv7 doesn't have the properties you think it does" , takes that assumption apart with a test you can reproduce. I still recommend UUIDv7. I just want you to know what you are signing.

TL;DR (for non-technical readers)

A new kind of ID number, UUIDv7, is popular because it keeps databases fast and still avoids collisions.

Each ID has the creation time baked in. That is handy, but it also means anyone who sees an ID can tell roughly when something was created, and the time is not always accurate.

It is a good internal label and a poor secret. Never use it as a password-like link.

Ask your tech team: "Do any of our public links, or any sorting logic, depend on these IDs being in time order?"

Why UUIDv7 is good

Random UUIDv4 values land all over a B-tree index.…