About ULID
A ULID is a 26-character identifier that is URL-safe and sortable by time: the first 10 characters encode the creation timestamp and the last 16 are random. This tool generates ULIDs in your browser with a secure random source.
How ULID Generator works
How to use it
- Choose how many to generate.
- Generate and copy the ULIDs.
How it works
Each ULID combines the current time (in Crockford base32) with random bytes. Because the timestamp comes first, ULIDs sort in creation order lexicographically — useful as database keys where ordering matters.
Common uses
- Generate sortable IDs
- Create time-ordered database keys
- Replace UUIDs with sortable IDs
- Make unique identifiers
- Generate keys for logs
- Create ordered tokens
- Bulk-generate ULIDs
- Get URL-safe IDs
Frequently asked questions
What is a ULID?
A 26-character, URL-safe, time-sortable unique identifier.
Why are ULIDs sortable?
The timestamp is encoded first, so they sort in creation order.
How long is a ULID?
26 characters.
Are they secure?
The random portion uses a secure random source.
Are my IDs uploaded?
No — they are generated in your browser.
How is the time encoded?
As Crockford base32 in the first 10 characters.
Is it free?
Yes — completely free with no sign-up.