PayloadPigeon

Test HTTP and WebSocket traffic in Chrome. Modify API responses and WebSocket messages, reproduce edge cases, save reusable tests.

PayloadPigeon helps developers test frontend and backend behavior using the real HTTP and WebSocket traffic their applications already generate. Instead of rebuilding requests from scratch, start Capture for the tab you want to test, perform the relevant action in your application, and inspect the resulting requests, responses, and WebSocket messages. Use PayloadPigeon to: • Capture HTTP requests, responses, and WebSocket traffic from the selected tab. • Inspect URLs, headers, bodies, status codes, and supported WebSocket messages. • Edit a captured HTTP request and send it to the backend again. • Modify a fresh HTTP response and see how the frontend reacts. • Modify, delay, or drop supported WebSocket messages and test related UI behavior. • Replay valid requests or responses without introducing artificial changes. • Save useful scenarios as reusable Tests. • Add Starting state and Expected behavior so the context stays with each Test. • Organize Tests into Test Plans for different application areas and scenarios. • Repeat saved checks while fixing a bug or after changing your application. • Record successful checks or problems as Results and keep useful technical evidence with them. PayloadPigeon supports both backend and frontend testing workflows. For backend checks, start from a request captured from your real application, edit it when needed, and send it to the destination server. For frontend checks, configure a supported HTTP response or WebSocket behavior, choose Ready, and repeat the relevant action in your application so the frontend receives the configured result. Capture is explicit: you choose the tab and start it yourself. Chrome may display a debugging notice while Capture is active because PayloadPigeon uses Chrome’s debugger API for browser-level network access on supported traffic. Local-first by design: core testing runs in your browser. Saved Tests, Test Plans, and Results are stored locally in encrypted storage protected by your PayloadPigeon password. No PayloadPigeon account or cloud synchronization is required for your saved library. Captured traffic can contain sensitive information such as URLs, headers, bodies, authentication data, and WebSocket messages. Captured traffic is not uploaded to PayloadPigeon for storage or analytics. Backend Send contacts only the destination you choose. The public PayloadPigeon Playground uses the demo service. Optional anonymous feature-usage analytics is disabled until you choose to enable it in Data & privacy. Analytics contains aggregate feature-use counts and does not include captured traffic. PayloadPigeon does not automatically execute an entire Test Plan. You choose and run each Test yourself. No application code changes are required. All features are available free during PayloadPigeon Early Access. Learn more, review data-handling details, watch the demo, and try the public Playground at payloadpigeon.com.