Online REST API Request Tester

What is the Online REST API Tester?

Our Online REST API Tester is a completely free, browser-based HTTP client that allows developers to send HTTP requests directly from their web browser. It serves as a lightweight, zero-installation alternative to heavy desktop applications like Postman or Insomnia. Whether you are debugging webhooks, testing third-party APIs, or interacting with RESTful services, this tool provides instant feedback.

Key Features

• Support for standard HTTP Methods: GET, POST, PUT, PATCH, DELETE, and HEAD.
• Custom Headers: Easily inject custom HTTP headers like Content-Type, Accept, or custom API keys.
• Bearer Token Auth: A dedicated input for Bearer tokens automatically formats your Authorization header securely.
• JSON Formatting: The request body input includes a one-click "Beautify JSON" feature to ensure your payloads are formatted correctly before sending.
• Local Execution: All requests are executed directly from your browser via the Fetch API. Your API keys and payload data are never logged to our servers.

Common Use Cases

• Testing Public APIs: Test endpoints from services like Stripe, GitHub, or JSONPlaceholder to see how they structure their response data.
• Debugging Webhooks: Replay or simulate webhook payloads to verify how your endpoint handles incoming POST requests.
• Verifying Authentication: Quickly test if a JWT or Bearer token is valid by hitting an authenticated endpoint.

Understanding CORS Limitations

Because this tool runs in the browser, it is subject to Cross-Origin Resource Sharing (CORS) restrictions. If you attempt to send a request to an API that does not return the appropriate Access-Control-Allow-Origin headers, your browser will block the request for security reasons. For testing local APIs (e.g., localhost:8080), ensure your local server is configured to allow CORS requests during development.