ULID Generator & Decoder

A ULID (Universally Unique Lexicographically Sortable Identifier) is a 26-character, Crockford base32-encoded identifier: a 48-bit millisecond timestamp followed by 80 bits of randomness. Unlike a random UUID v4, ULIDs sort chronologically as plain strings — handy for database primary keys, event logs, or anywhere you want unique, time-ordered, URL-safe IDs without a separate sequence column.

The alphabet deliberately excludes I, L, O, and U to avoid visual ambiguity (with 1 and 0) and accidental profanity. Everything on this page runs client-side — no ULID or timestamp you generate or decode here is sent anywhere.