While playing around with MQTT and testing applications it is always helpful to have a MQTT broker at hand. A public MQTT broker enables easy setups without setting up your own MQTT broker. We compiled a list of available brokers that can easily be used:
|iot.eclipse.org||Mosquitto||1883 / 8883||n/a|
|test.mosquitto.org||Mosquitto||1883 / 8883 / 8884||8080 / 8081|
Testing against public brokers also ensures that your application can handle various types of topics and payloads. Because most of those public brokers are actively used by many people and you will find lot of messages being published. Also, this will help you to verify that your code is compatible to different broker implementations
Please let us know if we are missing any brokers.