What is ULID Generator Online?
ULIDs solve the main weakness of UUID v4 for databases: they are not sortable. A ULID encodes a millisecond-precision timestamp in the first 10 characters, followed by 16 characters of cryptographic randomness. This makes ULIDs ideal for event logs, ordered feeds, and any system that benefits from natural chronological ordering without sacrificing uniqueness. This ulid generator online tool helps you create sortable, unique identifiers that increase database performance by reducing index fragmentation. Unlike UUIDs, which are scattered randomly across the disk, ULIDs are appended to the end of your B-Tree index, making inserts predictable and fast. The 128-bit compatibility with UUIDs means you can store them in standard UUID columns in databases like PostgreSQL while enjoying the benefits of timestamp-based sorting. They are also 26 characters long compared to the 36 characters of a standard UUID, making them more URL-friendly.
How to Use ULID Generator Online
- Click "Generate" to instantly produce a new ULID.
- The timestamp portion on the left encodes the current millisecond.
- Copy the result with the Copy button or click the value.
Example
A 26-character ULID
Output
01ARZ3NDEKTSV4RRFFQ69G5FAVDeveloper Tips
Use ULIDs as primary keys for audit logs or messaging systems where order matters. In JavaScript, you can use the `ulid` npm package for server-side generation.
Frequently Asked Questions
How does a ULID compare to UUID?
ULID is 26 characters vs 36 for UUID, is URL-safe (no hyphens), and sorts chronologically. UUID v4 is purely random and does not sort.
Is a ULID case-sensitive?
ULIDs are case-insensitive by spec. Uppercase is canonical, but lowercase variants are equivalent.