AscendLab

Developer tools

ULID Generator

Free browser tool

ULID Generator

Generate sortable ULIDs locally with timestamp prefixes and browser randomness for IDs, fixtures, and test data.

ULID Generator
Generate sortable 26-character ULIDs with timestamp prefix and browser randomness.
Generated IDs
Copy one ID per line.
Quick answer

ULIDs are sortable unique identifiers with a timestamp prefix.

This generator creates ULIDs locally for fixtures, logs, and non-security IDs.

Best inputs

Use modest batches

Generate only the number of IDs you need for a test or fixture.

Use server IDs in production

Production database IDs should usually be generated by your application or database.

ULID generation method
The tool combines current time with random characters.
The first 10 characters encode the current timestamp.
The final 16 characters use browser randomness.
Output uses Crockford Base32 characters.
Example, Assumption, and Limitation
Use the result as a practical estimate or transformation, then confirm edge cases for critical work.

Example

A ULID looks like 01HX... and is 26 characters long.

Assumption

IDs are for test data, fixtures, or local planning.

Limitation

This is not a replacement for authenticated server-side token generation.

Common use cases
These pages are built for lightweight browser-side work, examples, and planning.

Fixtures

Create sortable sample IDs.

Logs

Generate local event IDs.

Testing

Populate mock data.

Docs

Show realistic ID examples.

Frequently asked questions

What is a ULID?

A ULID is a 26-character identifier with a timestamp component and random component.

Are ULIDs sortable?

Yes. The timestamp prefix means ULIDs generally sort by creation time.

Does this use a backend?

No. ULIDs are generated in your browser.

Should I use this for security tokens?

No. Use purpose-built server-side token generation for authentication and security-sensitive workflows.

Suggested workflow

Identifier workflow

Generate ULIDs, compare UUIDs, then create hashes when needed.