Magic Tools
Developer ToolsBy CooconApril 22, 2026192 views2 min read

How to Use UUID Generator: Batch Generate v4 UUIDs and Switch Between Multiple Formats

What Scenarios is the UUID Generator Suitable For?

When doing interface testing, creating database demonstration data, preparing primary key samples, or generating tracking IDs, you often temporarily need a batch of UUIDs. Manually typing them is impractical, and opening the command line isn't always convenient.

At such times, an online UUID tool that can batch generate and support multiple formats is more handy.

What Does This Tool Support?

On the tools.cooconsbit.com/tools/uuid page, you can generate RFC 4122 v4 UUIDs and set:

  • Generation quantity 1 - 50
  • Lowercase / Uppercase
  • Standard hyphen format
  • Hyphen-free format
  • Brace format
  • URN format

After generation, you can copy all at once, copy individually, or delete any result.

How to Use It Most Conveniently?

For Interface or Database Testing

If you just want a few primary key samples, set the quantity, generate directly, then click Copy All.

For Meeting Different System Format Requirements

Some systems require hyphens, some require pure 32-character strings, and some configurations prefer brace format. Switching formats here is convenient, without needing to write scripts yourself.

For Preparing Documentation Examples

When writing technical documentation, interface descriptions, or SDK examples, you often need a batch of realistic, uniformly formatted UUIDs. Using an online tool is much faster than manually finding samples.

Points to Note

First, it generates v4 UUIDs.

Which are random UUIDs, suitable for most testing and common identification scenarios.

Second, although the formats differ, the essential value is still the same type of identifier.

For example, standard format and hyphen-free format are just different display methods.

Third, it is suitable for generating test or general business IDs.

If your system has requirements for ID sorting, readability, partitioning rules, etc., you need to design it separately based on the business.

Frequently Asked Questions (FAQ)

Q: Why are some UUIDs uppercase and some lowercase?

A: Usually, it's just different system habits or specifications; the tool supports switching between two output forms.

Q: Can it generate many at once?

A: The page currently supports batch generation, suitable for most testing and documentation scenarios.

Q: Are these UUIDs generated locally?

A: The page uses the browser's randomness to generate them, suitable for quick online use.

Summary

The key point of a UUID generator is not just 'being able to generate', but saving you the time of changing formats later. Quantity, case, and display format can all be set directly, and after copying, you can immediately put them into interfaces, database scripts, or example documentation.

Tool address: tools.cooconsbit.com/tools/uuid

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