ULID Generator -- Sortable Unique IDs
Generate ULIDs (Universally Unique Lexicographically Sortable Identifiers) instantly. Free online ULID generator with timestamp extraction and bulk generation.
Frequently Asked Questions
What is a ULID?
A ULID (Universally Unique Lexicographically Sortable Identifier) is a 128-bit identifier encoded as a 26-character Crockford Base32 string. It consists of a 48-bit timestamp and 80 bits of randomness. ULIDs are sortable, URL-safe, and more compact than UUIDs.
How is ULID different from UUID?
ULIDs are encoded in Crockford Base32 (26 characters vs UUID's 36), are lexicographically sortable, use no special characters (no hyphens), and are case-insensitive. Like UUID v7, they embed a timestamp, but ULIDs are more compact and URL-friendly.
Can I extract the timestamp from a ULID?
Yes. The first 10 characters of a ULID encode the Unix millisecond timestamp in Crockford Base32. This tool decodes and displays the creation timestamp for each generated ULID in human-readable format.
Are ULIDs suitable for database IDs?
Yes. ULIDs are excellent database identifiers because they are sortable by creation time (preserving index locality), globally unique, compact (26 characters), and contain no special characters. They are widely used as primary keys in modern databases.