UUID inspector

Validate and inspect an identifier

Paste a standard UUID, compact value, braced UUID, or UUID URN.

Choose the right UUID version

Random identifiers

Uses 122 random bits after version and variant fields. A strong default for independent identifiers.

Time-sortable IDs

Starts with a Unix millisecond timestamp and adds random bits, making database index locality friendlier.

Deterministic names

Hashes a namespace UUID and UTF-8 name with SHA-1. It is for reproducible IDs, not password security.

Legacy time-based IDs

Contains a Gregorian timestamp and node field. It can reveal generation time; v7 is often preferable for new systems.

Important UUID facts

Are UUIDs guaranteed unique?

No finite identifier has an absolute guarantee, but properly generated v4 collisions are extraordinarily unlikely. Applications still need appropriate unique constraints.

Is UUID v5 secure because it uses SHA-1?

v5 uses SHA-1 for standardized deterministic naming, not for signatures or password storage. Anyone with the namespace and name can reproduce it.

Are v7 UUIDs sequential?

They sort broadly by millisecond timestamp, while their remaining bits preserve randomness. They are not simple counters.

Does this tool upload generated IDs?

No. Generation, validation, formatting, and export happen locally in the browser.