Ulid Generator

What Is a ULID?

A ULID (Universally Unique Lexicographically Sortable Identifier) is a 128-bit identifier designed to provide uniqueness and time-based sorting. It is represented as a 26-character string using Crockford's Base32 encoding.

A ULID contains two parts:

• Timestamp: The first 48 bits represent the timestamp in milliseconds since the Unix epoch.

• Randomness: The remaining 80 bits provide randomness to help reduce the chance of duplicate identifiers.

Unlike sequential numeric IDs, ULIDs can be sorted lexicographically to reflect their creation time, provided the identifiers are compared using the appropriate ordering.

How to Use the Online ULID Generator

1. Choose a tool: Select ULID Generator to create new identifiers.

2. Enter the number of ULIDs: Specify how many identifiers you need.

3. Select a timestamp: Choose Current Time or Custom Date & Time.

4. Click Generate: Create the requested ULIDs using the selected timestamp.

The tool also includes a ULID Validator option for checking existing identifiers.

ULID Generator Example

Suppose you need three unique identifiers for database records or API resources.

Input

• Choose Tool: ULID Generator

• Number of ULIDs: 3

• Timestamp: Current Time

Output

These strings are illustrative examples, not verified output from the live generator. Use the actual ULIDs generated by the tool when publishing a real output example.

ULID vs UUID: What Is the Difference?

Both ULIDs and UUIDs identify records, objects, or resources in software applications. The main difference is that ULIDs include a timestamp in their structure, making them naturally sortable by encoded creation time. Standard UUID formats, such as UUIDv4, use random values and do not inherently encode a creation timestamp.

ULIDs are useful when time-based sorting is helpful, while UUIDs remain widely supported across databases, APIs, and programming languages.