CodeTools

Online tools for developers

Fast, lightweight, and private utilities — processed entirely in your browser.

100% in the browser · no data is sent to the server

JSON Formatter

Format, validate, and organize JSON instantly in the browser.

Useful for API responses, configuration files, and test fixtures.

UUID Generator

Generate v4 UUIDs for tests, fixtures, and development identifiers.

Uses Web Crypto and processes everything locally in the browser.

CPF Generator

Generate fictional, mathematically valid Brazilian CPF numbers for software tests.

No registry lookup, with an optional mask.

CNPJ Generator

Generate fictional, mathematically valid Brazilian CNPJ numbers for business tests.

No registry lookup, with an optional mask.
Quick guide and information

How to choose a tool

  1. Identify the task you need to finish.
  2. Read the tool description and examples.
  3. Use the result in your development workflow.

The portal is built for quick tasks: you do not need an account or to upload files to start.

When to use CodeTools?

Use the tools to review an API response, prepare test data, check a structure before a commit, or turn information into a format that is easier to read.

They complement your editor and terminal; they do not replace production validation or official sources.

Why CodeTools?

  • Extreme performance and no heavy dependencies
  • Privacy by design (client-side)
  • A straightforward interface for everyday work
  • Explanations and examples that reduce guesswork

Privacy

The tools process values in the browser whenever possible. What you type is not sent to CodeTools servers and is not saved by the portal. See our privacy policy to understand cookies and advertising.

FAQ

Do I need to install anything?

No. The tools work in a modern browser and do not require an account.

Can I use sensitive data?

Processing is local, but we still recommend not pasting secrets or personal data into any online tool.

Which tools are available?

The JSON Formatter and the UUID, CPF, and CNPJ generators are available now. New tools are listed only when they are ready to use.

More tools