UUID and ULID

Paste uuids, ulids or objectids — one per line — and the anatomy pulls out of every id, in your own browser, what the bits hold: version, variant, time, clock-seq, node address, machine id, counter and the random fields. No id leaves your machine.

The reading is bit-faithful: a UUIDv1 or v6 shows its Gregorian clock in milliseconds, a v7 its Unix time, a ULID its 48 time bits in ten Crockford characters, and two ULIDs together answer the monotone question. What the form does not carry — origin, ownership, real randomness — stays unclaimed.

You can also build one yourself: UUID v4 and v7, ULID and ObjectId, built from your browser CSPRNG with the version and variant nibbles placed where the standard puts them. Handy when you mint ids for your own application and want to see what the bits mean first.