What is WebSocket?
WebSocket is a communication protocol that provides full-duplex, persistent connections between a client and server over a single TCP connection. Unlike HTTP, which follows a request-response pattern, WebSocket allows both sides to send messages at any time after the initial handshake via ws:// or wss:// (TLS-encrypted).
How it works
A WebSocket connection starts with an HTTP upgrade request. Once upgraded, the connection stays open and both client and server can push frames - text or binary - without the overhead of new HTTP requests. The browser's WebSocket API handles framing, ping/pong keepalive, and close handshakes automatically.
How to use this tool
- Enter a WebSocket URL (e.g.,
wss://echo.websocket.org) and connect - Send text or JSON messages and see responses in real time
- Inspect the message log with timestamps, direction, and payload size
Common use cases
- Testing WebSocket server endpoints during development
- Debugging real-time features like chat, notifications, or live updates
- Verifying message formats and server responses
- Load-testing WebSocket connections with custom payloads
