ULID generator
Generate lexicographically sortable universally unique identifiers.
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About the ulid generator
Creates 26-character identifiers that encode a millisecond timestamp in the first ten characters and 80 bits of randomness in the rest. They sort chronologically as plain strings, use Crockford Base32 so there is no ambiguity between I, L, 1 and O, 0, and stay URL-safe.
Frequently asked questions
ULID or UUIDv7?
Both are time-sortable. ULIDs are shorter and case-insensitive in text form; UUIDv7 slots into existing UUID columns and library support without conversion. Pick UUIDv7 if your database has a native UUID type.
Do ULIDs leak information?
Yes — the creation time is readable by anyone holding the ID, and adjacent IDs reveal creation order. Do not use them where the timing of a record is sensitive.