> For the complete documentation index, see [llms.txt](https://docs.vernemq.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vernemq.com/1.7.1/configuration/websockets.md).

# Websockets

VerneMQ supports the WebSocket protocol out of the box. To be able to open a WebSocket connection to VerneMQ, you have to configure a WebSocket listener or Secure WebSocket listener in the `vernemq.conf` file first:

```
listener.ws.default = 127.0.0.1:9001

listener.wss.default = 127.0.0.1:9002
```

Keep in mind that you'll use MQTT-over-WebSocket, so you will need a Javascript library that implements the MQTT client behaviour. We have used the [Eclipse Paho client](https://eclipse.org/paho/clients/js/) as well as [MQTT.js](https://github.com/mqttjs/MQTT.js)

You won't be able to open WebSocket connections on a base URL, always add the `/mqtt` path.


---

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