API Tester
Test REST APIs with GET, POST, PUT, DELETE requests
Calculator
About API Tester
Test REST APIs directly from your browser. Enter a URL, select an HTTP method, add headers and body if needed, then click Send to see the response.
Note: Some APIs may not work due to CORS restrictions. For APIs that block browser requests, use the "Copy cURL" feature to test in a terminal.
How to Use
Test and debug REST APIs with custom headers, authentication, and request bodies
Enter API URL
Type or paste the full API endpoint URL including the protocol (https://).
Select HTTP Method
Choose the appropriate HTTP method: GET for fetching data, POST for creating, PUT/PATCH for updating, DELETE for removing resources.
Add Headers
Click "Add Header" to include custom headers like Content-Type, Accept, or custom API headers.
Configure Authentication
If the API requires authentication, select the auth type and enter your credentials (Bearer token, Basic auth, or API key).
Add Request Body
For POST/PUT/PATCH requests, add a JSON body in the Body section. The tool validates JSON syntax.
Send Request
Click "Send Request" to execute the API call and view the response with status, headers, and body.
Frequently Asked Questions
An API Tester is a tool that allows developers to send HTTP requests to REST APIs and view responses. It supports various HTTP methods (GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS), custom headers, request bodies, and different authentication types. It helps debug and test API endpoints during development.
CORS (Cross-Origin Resource Sharing) errors occur when a web browser blocks requests to a different domain for security reasons. This API Tester runs in your browser, so requests to APIs that do not allow cross-origin requests will fail. To test such APIs, use a backend proxy, browser extension, or desktop tools like Postman or Insomnia.
This API Tester supports four authentication methods: No Auth (for public APIs), Bearer Token (JWT or OAuth tokens), Basic Auth (username and password encoded in Base64), and API Key (custom header name and value). Choose the appropriate method based on your API requirements.
For POST, PUT, and PATCH requests, you can add a JSON body in the Body section. Make sure to set the Content-Type header to "application/json" (automatically added when you enter a JSON body). The tool validates your JSON syntax and will show an error if the format is invalid.
Yes, all requests are made directly from your browser to the target API. No data passes through our servers. Your request history and saved templates are stored in your browser's localStorage and never leave your device. However, be cautious when testing with sensitive credentials.
The "Copy as cURL" feature generates a cURL command that replicates your request. You can paste this command in a terminal to execute the same request outside the browser, which is useful for debugging CORS issues, sharing requests with teammates, or automating API calls in scripts.
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