Free Online API Testing Tool

A free online tool to test REST APIs with support for multiple HTTP methods, custom headers, and request body.

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5,760+

Total Calculations Run

< 15ms

Browser Execution Speed

100%

Client-Side Privacy

4.9 / 5.0

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About This Tool

This free online API testing tool allows developers to test REST APIs directly from their browser without any installation. It supports all major HTTP methods (GET, POST, PUT, DELETE, PATCH, HEAD, OPTIONS) and lets you customize request headers and body. The tool provides detailed response information including status code, response time, headers, and formatted response body. It's perfect for testing web services, debugging API integrations, or learning how APIs work.

Save your calculation history with a free account

How to Use

Select the HTTP method from the dropdown menu
Enter the API endpoint URL in the URL field
Add custom headers in the headers editor (optional)
Enter request body data in the body editor (optional)
Click the 'Send Request' button to test the API
View the response details including status, headers, body, and timing
Use the 'Clear' button to reset all fields
Use the 'Copy Response' button to copy response data to clipboard

Frequently Asked Questions

Find Quick Answers

Is this API testing tool really free?

Yes, this tool is completely free to use with no registration required. You can test as many APIs as you need without any limitations.

What HTTP methods are supported?

The tool supports GET, POST, PUT, DELETE, PATCH, HEAD, and OPTIONS methods - covering all standard REST API operations.

Can I test APIs with authentication?

Yes, you can add authentication headers (like Authorization: Bearer token) in the headers section to test authenticated APIs.

What data formats can I use for the request body?

You can send JSON, XML, form data, or plain text in the request body. The tool automatically sets appropriate Content-Type headers based on your input.

Are my API requests stored or logged?

No, all API testing happens entirely in your browser. No request data is sent to our servers or stored anywhere.

Need to run multiple calculations?

Create a free account today to unlock unlimited daily runs, access advanced parameters, save your history, and request custom features.

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