List of Public MQTT Brokers for Testing & Prototyping

Introduction

MQTT (Message Queuing Telemetry Transport) is a lightweight messaging protocol commonly used in IoT (Internet of Things) applications. Developers often need public MQTT brokers to test and prototype their IoT solutions without setting up a dedicated broker.

This article provides a list of publicly accessible MQTT brokers that can be used for development and testing. However, keep in mind that public brokers do not guarantee service reliability, as they are shared with multiple users. Use them responsibly and avoid overwhelming their resources.

What is an MQTT Broker?

An MQTT broker is a server that routes messages between MQTT clients. Clients can publish messages to specific topics, and other clients subscribed to those topics receive the messages. Public MQTT brokers allow users to test their IoT applications without needing to configure a local MQTT server.

Why Use a Public MQTT Broker?

Public MQTT brokers are useful for:

• Testing IoT devices and applications.
• Prototyping new MQTT-based services.
• Debugging connectivity issues.
• Learning about MQTT protocol features.

List of Public MQTT Brokers

Here is a list of freely available MQTT brokers for testing and prototyping:

1. Flespi MQTT Broker

• Address: mqtt.flespi.io
• Ports: 1883 (TCP), 80 (WebSocket), 8883 (SSL), 443 (Secure WebSockets)
• Type: Flespi
• Info: Requires signup, supports MQTT 5.0, REST API, cloud-based service.

2. Mosquitto Public Broker

• Address: test.mosquitto.org
• Ports: 1883, 8883 (SSL), 8884 (SSL), 80 (WebSockets)
• Type: Mosquitto
• Info: Free and open-source broker, widely used, WebSocket support available.

3. HiveMQ Public Broker

• Address: broker.hivemq.com
• Ports: 1883, 8000 (WebSockets)
• Type: HiveMQ
• Info: Provides statistics and dashboard for monitoring MQTT messages.

4. CloudMQTT

• Address: www.cloudmqtt.com
• Ports: 18443, 28443 (SSL)
• Type: Mosquitto
• Info: Requires signup, offers a free plan.

5. Dioty MQTT Broker

• Address: mqtt.dioty.co
• Ports: 1883 (MQTT), 8883 (MQTT+SSL), 8080 (WebSockets), 8880 (WebSockets+SSL)
• Type: Mosca
• Info: Free with signup, supports mobile IoT applications.

6. Swifitch MQTT Broker

• Address: mqtt.swifitch.cz
• Ports: 1883 (MQTT)
• Type: Mosquitto
• Info: Free, runs on Raspberry Pi VPS, primarily for Swifitch projects.

7. Bevywise MQTT Broker

• Address: broker.bevywise.com
• Ports: 1883 (TCP), 8443 (WebSockets)
• Type: Bevywise
• Info: Requires signup, offers a free trial.

8. Fluux MQTT Broker

• Address: mqtt.fluux.io
• Ports: 1883 (TCP), 8883 (TLS)
• Type: Ejabberd
• Info: Free, no registration required, supports MQTT 5.0.

9. Solace Cloud MQTT Broker

• Address: console.solace.cloud
• Ports: Varies (TCP, TLS, WS, WSS)
• Type: Solace
• Info: Requires signup, offers a free plan with up to 50 connections.

10. MyQttHub Public Broker

• Address: node02.myqtthub.com
• Ports: 1883 (TCP), 8883 (SSL), 443 (Web, REST API)
• Type: MyQtthub
• Info: Requires signup, supports REST API.

11. Emqx Public Broker

• Address: broker.emqx.io
• Ports: 1883 (MQTT), 8883 (SSL), 8083 (WebSockets)
• Type: EMQX
• Info: Free, cloud-based, supports WebSockets and MQTT 5.0.

12. Eclipse IoT MQTT Broker

• Address: iot.eclipse.org
• Ports: 1883 (MQTT), 8883 (SSL)
• Type: Mosquitto
• Info: Provided by Eclipse IoT, widely used for IoT research and development.

13. Thingsboard MQTT Broker

• Address: demo.thingsboard.io
• Ports: 1883 (MQTT), 8883 (SSL)
• Type: ThingsBoard
• Info: Requires signup, provides dashboards and analytics tools for IoT devices.

14. Crysk MQTT Broker

• Address: mqtt.crysk.net
• Ports: 1883 (MQTT), 8883 (SSL), 8080 (WebSockets)
• Type: Crysk
• Info: Free and community-supported, includes monitoring tools.

15. TagoIO MQTT Broker

• Address: mqtt.tago.io
• Ports: 1883 (MQTT), 8883 (SSL)
• Type: TagoIO
• Info: Requires signup, integrates with IoT dashboards and cloud services.

Considerations When Using Public Brokers

While public MQTT brokers are helpful, they have limitations:

• No guaranteed uptime: These brokers can experience downtime or latency issues.
• Limited security: Messages are often unencrypted unless you use SSL/TLS.
• Resource sharing: Many users connect to the same broker, leading to congestion.
• Data retention policies: Some brokers do not store retained messages.

For long-term or production use, consider setting up a dedicated MQTT broker using Mosquitto, EMQX, or HiveMQ on your server.

Conclusion

Public MQTT brokers provide a valuable service for developers and hobbyists looking to test IoT applications. While they should not be relied on for mission-critical applications, they are great for prototyping and learning. Choose the right broker based on your requirements, such as WebSocket support, MQTT version compatibility, and security features.

Read This: Top Alternatives to Mosquitto MQTT Broker