ULID Generator
Generate sortable, timestamp-based ULIDs with secure randomness.
Sortable unique IDs
A ULID is a modern alternative to the UUID: a compact, URL-safe identifier whose leading characters encode the creation time, so a list of ULIDs naturally sorts into chronological order. That makes them friendlier for database indexes.
Each ULID is 26 Crockford Base32 characters — a 48-bit timestamp followed by 80 bits of randomness. Generate a batch and you will see they share a prefix that advances with time.
Secure and private
The random portion uses crypto.getRandomValues, and the whole ID is built in your browser with nothing uploaded.
Frequently Asked Questions
What is a ULID?
A Universally Unique Lexicographically Sortable Identifier: a 26-character Crockford Base32 string whose first part encodes the time, so ULIDs sort in creation order.
How is it different from a UUID?
A UUID is random and unordered; a ULID embeds a millisecond timestamp, making it sortable and index-friendly while staying collision-resistant.
Is the randomness secure?
Yes — it uses crypto.getRandomValues, the browser’s cryptographically secure source, for the random portion.
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