Web Client SDK

Version: 2.0.0

Released on Oct 22, 2021


The MQTT.Cool Web Client is a JavaScript library for the development of MQTT.Cool clients running inside any web browser.

The library enables any HTML page to act as an MQTT client; that is, ready to send and receive real-time MQTT messages to/from any MQTT broker connected through the MQTT.Cool server.


Compatible with MQTT.Cool Server since 1.2.0.
Based on Lightstreamer SDK for Web Clients version 8.0.3 build 1800.



The library is available as npm package, so you can download and install it through:

$ npm install


The library is also available on unpkg, to which you can point directly in the script tag:

<script src=""></script>


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