REST API Tester
Functional, client-side HTTP client to compose, inspect, and test REST endpoints with custom methods, headers, parameters, and payloads.
Interactive HTTP Request Composer
Select method, add headers, parameters or JSON payload, and execute requests directly in browser.
No query parameters defined.
Client-Side HTTP API Request Testing & Inspection
Testing backend REST API endpoints, webhooks, or microservices often requires firing quick HTTP requests with specific headers, auth tokens, or JSON bodies. Switching to heavy desktop applications or command-line utilities can disrupt workflow speed during quick developer smoke tests.
The REST API Tester provides a lightweight, instant browser-based client to compose requests across all HTTP verbs (GET, POST, PUT, DELETE, PATCH), set headers and query parameters, supply request payloads, inspect structured response outputs, and export ready-to-run cURL and Fetch code snippets.
Core Tool Capabilities
- Multi-Method Request Composer: Support for GET, POST, PUT, DELETE, PATCH, HEAD, and OPTIONS request execution.
- Headers & Query Param Builder: Easily attach dynamic query string parameters and custom request headers.
- Authentication Helpers: Configure Bearer Tokens, Basic Auth credentials, and custom API key headers.
- cURL & Code Exporters: Generate copyable command-line cURL or JavaScript fetch code snippets instantly.
Local Browser Privacy
Your files are processed locally on your device. Files are not uploaded, transmitted, or stored on remote servers.
Once the page has loaded, you can disconnect your network connection and continue using this tool offline.
Target Use Cases
- • API Smoke Testing
- • Webhook Endpoint Debugging
- • Authentication Token Testing
- • Code Snippet Generation
Technical Specifications & Platform Limits
Full HTTP request method coverage
Ready for terminal execution or application code
Runs directly inside your modern web browser
Requests pass directly from client browser to target endpoint
Step-by-Step Workflow
Enter Endpoint URL
Provide the destination API URL and select the desired HTTP method from the dropdown.
Configure Request Parameters
Add custom query search parameters, headers, or authentication tokens in the configuration tabs.
Add Request Body (If Applicable)
For POST, PUT, or PATCH methods, choose JSON or raw text and supply the payload.
Send & Inspect Response
Click 'Send Request' to execute and inspect status codes, latency timings, and formatted response data.
Practical Real-World Use Cases
API Smoke Testing
Developers verify backend service health, endpoint routes, and return codes quickly.
Webhook Endpoint Debugging
Developers dispatch test payloads to public endpoints like Httpbin or JSONPlaceholder.
Authentication Token Testing
Developers validate Bearer token headers and API authorization responses.
Code Snippet Generation
Developers export clean cURL commands for terminal testing or documentation sharing.
Frequently Asked Questions
- How does the REST API Tester handle CORS restrictions?
- Because requests are dispatched directly from your browser, target endpoints must support Cross-Origin Resource Sharing (CORS) headers. For CORS-restricted servers, you can export the generated cURL command to execute directly in your terminal.
- Are my API keys or payloads stored on any remote server?
- No. All request composition, header generation, and HTTP execution happen exclusively inside your local browser instance with No intermediary logging or telemetry.
- Can I test JSON request payloads?
- Yes. Select 'JSON' in the Body tab, enter your request object, and the client automatically attaches the 'Content-Type: application/json' header.
- Does this client support URL query parameters?
- Yes. Adding key-value pairs in the Query Params tab automatically formats and appends them to the destination URL.
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Master this tool with Guides & Articles
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