What is ULID?
ULID (Universally Unique Lexicographically Sortable Identifier) is a 128-bit identifier that combines a timestamp with randomness. Unlike UUIDs, ULIDs are sortable by creation time.
ULID Format
A ULID consists of 26 characters using Crockford's Base32 encoding:
- First 10 characters: Timestamp (48 bits, millisecond precision)
- Last 16 characters: Randomness (80 bits)
ULID vs UUID
ULIDs offer several advantages over UUIDs: they're lexicographically sortable, encode creation time, and use a URL-safe character set without special characters.