A short companion for ULID Generator: when it is useful, what it expects, and what to check before using the result.

What it does

ULIDs are 128-bit identifiers like UUIDs, except the first 48 bits are a millisecond timestamp. That makes them sortable by creation time while staying unique, which is handy as a primary key when you want insertion order without keeping a separate timestamp column.

Use the tool

Open ULID Generator, add the input the tool asks for, run it, and check the output before using it elsewhere.

Input and output

  • Input: text.
  • Output: text.
  • Category: Crypto.

Privacy and processing

Processing happens locally in your browser. This tool does not upload the input to ilham.dev.

Questions

Should I use a ULID or a UUID?

ULIDs if you want keys that sort by creation time and stay roughly chronological. UUIDs if you need the widest possible support, or must not reveal when a record was created.

Are ULIDs case-sensitive?

The canonical form is uppercase Crockford Base32, and that is what this tool produces.

Related guide

For broader background, see IDs and Test Data.