API Tester & REST Client

Ultimate API testing tool for developers. Send GET, POST, PUT, DELETE, PATCH requests with custom headers, authentication, and request body. Features include history tracking, environment variables, code generation, and cURL import.

API Client Ultimate

History
No requests yet
Query params are managed directly in the URL bar.
Response

Ready to send request

API CLIENT READY
UTF-8

What is API Tester & REST Client?

Ultimate API testing tool for developers. Send GET, POST, PUT, DELETE, PATCH requests with custom headers, authentication, and request body. Features include history tracking, environment variables, code generation, and cURL import. This tool is designed to make your development workflow faster and more efficient.

How to Use API Tester & REST Client

  1. Paste or upload your data - Copy and paste your content, upload a file, or use the sample data to get started.
  2. Configure your preferences - Choose formatting options like indentation size, sorting, or output format.
  3. Process with one click - Click the Format, Validate, or Minify button to process your data instantly.
  4. Copy or download results - Copy the output to clipboard with one click or download as a file for later use.

Why Use Our API Tester?

Our API Tester is optimized for speed, accuracy, and ease of use. Unlike other tools, everything runs locally in your browser with no data sent to external servers.

100% Free

No hidden charges, subscription fees, or watermarks. Use all features completely free.

🔒

100% Private

All processing happens locally in your browser. Your data never leaves your device or reaches any server.

Lightning Fast

Instant results with no server delays. Process large datasets in milliseconds directly in your browser.

Key Features

Works entirely offline
No account or signup required
Processes data instantly
Results saved in browser cache
Mobile-friendly interface
Works with modern browsers

Common Use Cases

This API Tester is perfect for:

  • Quick development tasks
  • Testing and validation
  • Data transformation
  • Format conversion
  • Learning and education
  • Production-ready quality

Frequently Asked Questions

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