How to use WebSocket Tester
- Enter the WebSocket URL (wss:// on HTTPS pages) and press Connect.
- Type a message (text or JSON) and press Send or Ctrl/⌘+Enter.
- Watch incoming frames in the log; toggle JSON pretty-printing as needed.
- Enable auto-reconnect or keep-alive to test resilience, then Disconnect when done.
WebSocket Tester features
- Connect to ws:// and wss:// servers directly from the browser, with optional sub-protocols
- Timestamped log of sent and received frames with direction, size and JSON pretty-printing
- Auto-reconnect with exponential back-off and an optional keep-alive message
- Close code and reason reporting, clean/unclean close detection
- Copy or download the log for bug reports
WebSocket Tester example
Echo test
Input:
wss://echo.websocket.org
{"type":"ping","id":1}Output:
12:00:01.120 • info Connected
12:00:03.410 ▶ sent {"type":"ping","id":1}
12:00:03.655 ◀ recv {
"type": "ping",
"id": 1
}Frequently asked questions about WebSocket Tester
Where does the connection come from?
Directly from your browser to the server — nothing passes through Mutqan. Use wss:// on this HTTPS page; browsers block plain ws:// except to localhost.
Can I send custom headers?
Browsers do not allow custom headers on WebSocket handshakes. Use query parameters, a sub-protocol value or an in-band auth message instead.
What does auto-reconnect do?
After an unexpected close it reconnects with exponential back-off (1 s, 2 s, 4 s … up to 30 s, 10 attempts). Manual disconnects do not trigger it.
Can I keep the connection alive?
Enable the keep-alive option to send a message of your choice every N seconds while connected.
Technical notes
The browser WebSocket API cannot set custom headers or inspect handshake responses; authentication must use query parameters, sub-protocols or an application-level message. Binary frames are logged with their size.