UUID v4 generator

Generate unique identifiers for development, tests, and fixtures directly in the browser · 100% client-side · no values are sent to the server

Generated UUIDs

You can generate 1 to 10 UUIDs at a time. The limit keeps the tool fast and the result easy to review.

Quantity

Quick guide and information

How to use

Choose how many UUIDs you need, from 1 to 10.
Click Generate UUID to create new values.
Copy the list and use it in fixtures, tests, or development data.

When to use

Use UUIDs when a test needs distinct identifiers, when a fixture needs to simulate several records, or when a prototype needs IDs without depending on a database.

They are also useful for representing resources in API examples and distributed systems.

What is UUID v4?

A UUID is a 128-bit identifier, usually shown as 36 hexadecimal characters separated by hyphens. Version 4 uses random values and reserves bits to indicate the identifier version and variant.

CodeTools uses the browser Web Crypto API, preferring crypto.randomUUID() and falling back to a compatible crypto.getRandomValues() path.

Practical cases

Create disposable IDs for automated test fixtures.
Fill API payload examples without using real data.
Simulate different entities in a local prototype.

Limitations and security

UUID v4 is not a password, authentication token, or secret. Do not use it to protect resources, sign requests, or replace an authorization mechanism.

Randomness reduces collisions, but it is not an absolute uniqueness guarantee in every system.

FAQ

Are the UUIDs sent to a server?

No. Generation happens in the browser and CodeTools does not store the values.

Which version is generated?

The tool generates UUID v4, intended for random identifiers in development and tests.

Can I generate a secret token?

No. A UUID should not be treated as a secret or security credential.