An MQTT broker, which is the heart of the MQTT Publish/Subscribe protocol, is a server that receives all messages from the MQTT clients and then routes the messages to the appropriate subscribing clients. We host a free online public MQTT broker and HiveMQ MQTT WebSocket client to make it easy for you to experiment with MQTT messages. To evaluate an enterprise-ready MQTT broker, check out HiveMQ MQTT broker.
Public MQTT Broker
Our Public HiveMQ MQTT broker is open for anyone to use. Feel free to write an MQTT client that connects with this broker. We have a dashboard so you can see the amount of traffic on this broker. We also keep a list of MQTT client libraries that can be used to connect to HiveMQ.
You can access the broker at: