Response
Response Headers
Response Body
Free REST API Tester Online
Test your APIs directly from your browser — no installations needed
Our free REST API Tester allows you to send HTTP requests to any API endpoint and inspect the response. Support for all HTTP methods (GET, POST, PUT, PATCH, DELETE), custom headers, request bodies, and real-time response analysis. Whether you're debugging an API, validating endpoints, or learning RESTful architecture, this tool provides everything you need — entirely in your browser.
📡 What is a REST API?
A REST (Representational State Transfer) API is an architectural style for designing networked applications. REST APIs use standard HTTP methods like GET, POST, PUT, PATCH, and DELETE to interact with resources. They communicate using formats like JSON or XML and follow stateless client-server architecture, making them the backbone of modern web and mobile applications.
🛠️ How to Use This REST API Tester
- 1 Select the HTTP method (GET, POST, PUT, PATCH, or DELETE) from the dropdown.
- 2 Enter the full API endpoint URL including the protocol (https://).
- 3 Add custom request headers in JSON format (e.g., Content-Type, Authorization).
- 4 For POST/PUT/PATCH requests, enter the request body in JSON format.
- 5 Click 'Send Request' to execute and inspect the response status, headers, and body.
✨ Key Features
All HTTP Methods
Support for GET, POST, PUT, PATCH, and DELETE — test any RESTful endpoint with the correct HTTP verb.
Custom Headers
Add authentication tokens, content types, and custom headers to your requests in a flexible JSON format.
Full Response Analysis
View response status codes, headers, body content, and response time — everything you need to debug APIs.
🎯 Common Use Cases
🐛 API Debugging
Quickly test and debug API endpoints during development. Inspect response payloads, verify status codes, and identify issues without writing any code.
✅ Endpoint Validation
Validate that your API endpoints return the correct HTTP status codes, response headers, and data structures before deploying to production.
📚 Learning REST APIs
Perfect for beginners learning RESTful architecture. Experiment with public APIs and understand how HTTP methods, status codes, and headers work in practice.
🔗 Third-Party Integration
Test third-party APIs like Stripe, Twilio, or OpenAI before integrating them into your application. Verify authentication flows and response formats.
💡 Best Practices for REST API Testing
- Always include the Content-Type header (application/json for JSON payloads) to ensure proper request formatting.
- Use Bearer tokens in the Authorization header for APIs that require authentication.
- Start with GET requests to understand the API response structure before sending POST/PUT requests.
- Validate response status codes — 200 (OK), 201 (Created), 400 (Bad Request), 401 (Unauthorized), 404 (Not Found), 500 (Server Error).
- Check response headers for rate limiting information (X-RateLimit-Remaining) to avoid API throttling.
- Always test error scenarios — send invalid data, missing fields, or wrong authentication to verify proper error handling.
❓ Frequently Asked Questions
Is it safe to test APIs with this tool?
Yes. All requests are sent directly from your browser to the API endpoint. We don't store, log, or intercept your requests or responses. However, be cautious when testing with sensitive credentials — always use test/staging environments for APIs requiring production keys.
Can I test APIs that require authentication?
Absolutely. Add your Authorization header with Bearer tokens, API keys, or Basic auth credentials in the request headers field. The tool supports any custom header your API requires.
Why am I getting CORS errors?
CORS (Cross-Origin Resource Sharing) errors occur when the target API doesn't allow requests from browser-based tools. This is a security feature of web browsers. To work around this, you can use a CORS proxy, test with APIs that support CORS, or use the tool in a backend testing workflow.
What HTTP methods are supported?
This tool supports all standard HTTP methods: GET (retrieve data), POST (create resources), PUT (update/replace resources), PATCH (partial updates), and DELETE (remove resources). Each method corresponds to a standard CRUD operation.
Can I test APIs with file uploads?
This tool is designed for JSON-based API testing. For file uploads with multipart/form-data, you'll need a more specialized tool like Postman or cURL. However, you can test APIs that accept base64-encoded file content in JSON payloads.