WebSocket Tester — Free Online WebSocket & SSE Client
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WebSocket Tester

Connect to WebSocket and SSE endpoints, send messages, and inspect frames in real time.

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About WebSocket Tester

Test WebSocket and Server-Sent Events (SSE) endpoints directly in your browser — no install required. Connect, send messages, and inspect every frame in real time. Supports subprotocols, auto-ping, and JSON pretty-printing.

WebSocket Tester

WebSocket Tester is a free, client-side tool designed to help developers with connect to websocket and sse endpoints, send messages, and inspect frames in real time..

How to Use

  1. Input your data into the primary editor or upload a file.
  2. Adjust any necessary configuration options.
  3. View the output in real-time or click the action button to process.
  4. Copy or download the results securely.

Privacy First

All processing happens directly in your browser. We never send your sensitive data to our servers.

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