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ULID Generator

Generate ULIDs (Universally Unique Lexicographically Sortable Identifiers) — 26-char Crockford base32 encodings of 48-bit timestamp + 80-bit random

Generate between 1 and 1000 ULIDs

ULID format: 01ARZ3NDEKTSV4RRFFQ69G5FAV (26 chars). First 10 chars encode the Unix timestamp (ms); last 16 are random Crockford Base32.

ULIDs sort lexicographically by time, making them ideal for database indexes and event logs where insertion order matters and UUIDs of the same major version (v4) would produce random sort order.

Monotonic mode increments the random portion by 1 when multiple ULIDs share the same millisecond, guaranteeing strict ascending order even within a tight burst.