What is ULID Generator?

ULID Generator is a tool for creating ULIDs directly in the browser. A ULID is a unique identifier that is easier to sort by time than a UUID, while also being shorter and easier to read in many cases.

This tool lets you try not only the standard generation mode, but also time-seeded and monotonic generation. That makes it useful when you want to compare how different ULID generation methods behave.

How to Use

1. Choose a generation method.
2. Enter a seed time when the selected method requires it.
3. Set how many ULIDs you want to generate.
4. Run the generator and review the result.

For many cases, the default method is enough. If you want to test fixed times or generation order within a short interval, the other methods are helpful.

Generation Methods

Default

Generates a normal ULID based on the current time. This is the simplest option and usually the best place to start.

Time Seed

Generates ULIDs based on a specified time value. Useful when you want to test IDs against a fixed timestamp or generate values using the same time reference.

Monotonic

Generates ULIDs in a way that is more stable for ordering when multiple IDs are created within the same timestamp window. It is useful when you want to test rapid sequential generation.

ULID Features

• 26 characters long and relatively compact
• Includes timestamp information, making time-based ordering easier
• Uses characters that work well in URLs and file names
• Easy to evaluate as an alternative to UUID in some systems

Use Cases

• Creating IDs for logs or events that you want to sort by time
• Testing ULID as a candidate key for a database
• Generating unique identifiers for distributed systems or APIs
• Comparing the practical differences between ULID and UUID

Things to Keep in Mind

• Methods other than the default require a seed time
• The ordering behavior can differ depending on which generation method you choose
• Even if ULID is easier to handle visually, it is still worth checking whether it fits your storage model and system design before adopting it

Note

ULID combines a timestamp component with a random component. It is often chosen when you want both easier chronological sorting and a shorter visual format than UUID. For specification details, see the ULID specification.