Free Browser REST API Request Tester
Send request payloads and analyze JSON responses — a lightweight Postman alternative.
Debug HTTP Endpoints Instantly in Your Browser
Developers and QA engineers constantly need to inspect API endpoints. Our free online API tester provides a clean client-side platform to configure headers, body parameters, and send GET, POST, PUT, PATCH, and DELETE requests.
Inspect formatted JSON responses, query headers, status codes, and roundtrip latency times without installing heavy native desktop apps.
Key Benefits & Features
Formatted Response View
Dynamic syntax highlighting for response JSON payloads.
Headers & Body Editor
Customize headers and send raw text, JSON, or form-data payloads.
How to Use the API Tester Step-by-Step
This utility runs entirely inside your browser using client-side JavaScript. We prioritize your security: none of your inputted text is logged or stored.
- 1
Enter the target API endpoint URL.
- 2
Select the HTTP method and specify any headers or body parameters.
- 3
Click Send and view the detailed response codes, timing, and JSON output.
Practical Examples
POST https://api.site.com/v1/user with Body {"name":"test"}
Frequently Asked Questions (FAQ)
Why am I seeing a CORS error?▼
CORS (Cross-Origin Resource Sharing) is a security mechanism. If the target server does not send headers allowing requests from tools.doosix.in, your browser blocks the response. You must configure CORS on the target server.
Are my headers or API keys stored?▼
No. All network requests originate directly from your browser client, ensuring keys and credentials remain private.
Ready to boost your productivity?
Browse our full list of free developer utilities and make your daily content, coding, or math tasks easier.