FAQ

What is MQTTX Web?

MQTTX Web is a free, open-source (Apache-2.0) MQTT 5.0 client that runs in the browser. It connects to MQTT brokers over WebSocket, so you can test MQTT without downloading or installing anything. Open it at mqttx.app/web-client.

Which MQTT versions and protocols does MQTTX Web support?

MQTTX Web supports MQTT 5.0 and 3.1.1 over MQTT over WebSocket (ws:// and wss://). Browsers cannot open raw TCP connections, so MQTT over TCP and TLS on ports such as 1883 and 8883 are not supported. Use MQTTX Desktop or MQTTX CLI for those.

Why can't I connect with ws:// on the hosted version?

The hosted MQTTX Web is served over https://, and browsers block insecure ws:// connections from secure pages. Use wss:// instead, or deploy MQTTX Web yourself over http://. See Differences Between Web and Desktop Versions.

Does MQTTX Web support mutual TLS?

MQTTX Web cannot configure client certificate and private key files for mutual (two-way) TLS authentication. Use MQTTX Desktop or MQTTX CLI when you need to supply these files.

Can I deploy MQTTX Web on my own server?

Yes. Run the official Docker image:

docker run -d --name mqttx-web -p 80:80 emqx/mqttx-web

You can also build it from source and change defaults such as the broker address and base URL. See Development.

How is MQTTX Web different from MQTTX Desktop?

Creating connections, subscribing, and publishing messages follow the same basic workflow, but Web supports only WebSocket connections and requires wss:// when served over HTTPS. It cannot configure client certificate files, and Desktop features such as MQTTX Agent and Viewer are not available. See Web Get Started for the differences and deployment options, and the Desktop Get Started guide for the shared workflow.