MQTT basics

10 Best MQTT Tools for Your IoT Project

Philipp Struss10.01.202421.01.2025

In today’s Internet of Things (IoT) landscape, the MQTT protocol serves as a cornerstone for driving IoT application innovation. Developers worldwide are leveraging different tools to make the MQTT broker implementation smoother. These MQTT tools make it easier to connect to the broker, publish messages, and subscribe to topics. They also simplify testing and debugging the MQTT broker. In this article, I’ll cover the most popular MQTT client tools available for various platforms.

Download the Pro Mosquitto MQTT broker

To use the MQTT client tools described below, you must first install an MQTT broker. I recommend the Pro Edition for Mosquitto™, a secure, intuitive, and easy-to-use MQTT broker. Sign up for a Cedalo MQTT Platform trial to experience the benefits of working with a professional-grade broker, complete with an intuitive Management Center for Mosquitto web UI.

MQTT tools overview

The MQTT toolset offers various options for developers and IoT data experts seeking to manage and evaluate MQTT brokers and client applications. The comparison table below showcases the most popular MQTT client tools to help you find the right fit for your IoT application.

1. MQTT Explorer

MQTT Explorer is a popular tool with an intuitive user interface for testing MQTT brokers. It allows you to view all server threads and can handle hundreds of thousands of MQTT messages per minute.

MQTT Explorer features

• Subscribe to topics
• Publish topics
• Create digital themes
• Visualize messages hierarchically
• Search topics
• Delete saved topics
• Delete topics recursively
• Compare current and historical messages for differential analysis

MQTT Explorer Installation

MQTT Explorer is available for Linux, Windows, and MacOS. Go to mqtt-explorer.com and download the appropriate version for your system. Then, run the file and follow the instructions to complete the installation.

2. Management Center for Mosquitto™

The Management Center for Mosquitto™ is a web UI that allows you to manage Pro Mosquitto broker instances and High Availability (HA) clusters. It offers detailed monitoring metrics, robust security features, and an integrated MQTT Client UI functionality that allows you to test various MQTT operations.

MMC features

• View MQTT broker instance settings
• Review broker performance metrics (e.g., messages sent/received, number of connected clients, etc.)
• Detailed overview of all MQTT client connections
• Visualize the entire hierarchy of topics and sub-topics
• Manage client accounts
• Arrange clients into groups
• Assign roles and Access Control Lists (ACLs) to clients
• Review active client certificates
• Create topic streams
• Monitor MQTT operations in real-time (e.g., create topics, publish/subscribe messages, etc.)

MMC installation

The simplest way to test the Management Center’s functionality is by signing up for a Cedalo MQTT Platform trial. You can install the Management Center on Windows, Linux, or MacOS following the instructions in this article.

3. MQTTBox

MQTTBox is a cross-platform application that allows the creation and testing of MQTT clients, virtual device networks, and load testing of MQTT brokers and devices.

MQTTBox features

MQTT clients can:

• Connect MQTT clients to one or more brokers
• Create subscriptions to multiple topics for one MQTT client
• Post messages to several different topics from one client
• Provide single-level and multi-level subscriptions to topics
• Save message history for each topic
• Support TCP, SSL/TLS, and WebSockets
• Copy and republish the payload
• Set up MQTT clients

MQTT load can:

• Perform load testing of MQTT devices and a broker
• Set up load testing of the publication and subscription to the topic
• Provide an extensive set of load test settings (e.g., number of MQTT messages to publish/subscribe per second, number of instances to reach, etc.)
• View the progress of connecting/disconnecting to the MQTT broker and publishing/subscribing to topics in real-time
• Create graphs to view the results of the load testing
• Overview sent/received load test data

MQTTBox installation

It is possible to install MQTTBox as a Chrome web application, a Windows application, or as an add-on for the Google Chrome browser.

• The Windows application is available on the Microsoft Store.
• To install the program as a browser extension, go to Chrome Web Store and add it to your browser. Then, you can access it from the Chrome apps page.

You can also download the application’s source code from GitHub and modify it to suit your needs.

4. Mosquitto_pub and Mosquitto_sub

Mosquitto_pub is a command line utility that allows you to create MQTT clients and post messages to topics.

Mosquitto_sub is an MQTT client that allows you to subscribe to topics, print and filter received messages, and unsubscribe from topics.

Mosquitto_pub and Mosquitto_sub features

• Set up a pub/sub to topics.
• Publish/subscribe in debugging mode.
• Subscribe to all topics at once.
• Connect to the broker using a username and password.
• Provide client id prefix.
• Publish JSON data.
• Support using a certificate file.
• Save published messages.
• Delete saved messages.
• Support settings, including host, port, timeout, etc.

Mosquitto_pub and Mosquitto_sub Installation

To install mosquitto_pub and mosquitto_sub, you must install Mosquitto clients for MQTT brokers.

Windows

To install Mosquitto clients on Windows, download the installation file from mosquitto.org. Run the saved file and follow the instructions to install Pro Mosquitto MQTT broker and Mosquitto clients.

You can install Mosquitto clients on Linux using the command line by running the following command:

sudo apt-get install mosquitto-clients

For Linux distributions that support snap, you can use the following command:

sudo snap install mosquitto

MacOS

To install Mosquitto clients on MacOS, you can use the homebrew project and run the following command:

brew install mosquitto

5. Mosquitto_rr

Mosquitto_rr is an MQTT client that supports the Request-Response feature of MQTT v5. This allows you to publish a request message and wait for a response.

Mosquitto_rr features

• Support TLS-encrypted connections
• Working in debug mode
• Transfer the response topic to the broker
• Utilization of certificate files
• Sending file content as a request message
• User authorization using username and password
• Choosing the quality of service (QoS)
• Message filtering
• Support for a large number of settings

Mosquitto_rr installation

Windows

To install mosquitto_rr on Windows, download and run the installation file from mosquitto.org. 

Linux

Run the following command to install mosquitto_rr on Linux:

sudo apt-get install mosquitto-clients

Or use the following command for Linux distributions that support snap:

sudo snap install mosquitto

MacOS

Use the homebrew project and the following command to install mosquitto_rr on macOS:

brew install mosquitto

6. MQTT.fx

MQTT.fx is a desktop tool for testing MQTT broker performance.

MQTT.fx features

• Publish/subscribe functions
• Supports $SYS themes
• Save multiple connection configurations
• Supports multiple types of encryption methods
• Establish a single connection at a time
• JavaScript scripting support
• Mime-Type support in messages
• Authorization using a username and password
• SSL/TLS support
• Provide predefined message templates
• HTTP proxy support
• Store recent topic history
• Automatic update search

MQTT.fx installation

Download the MQTT.fx installation file from the official website, then run the file and follow the instructions to complete the installation.

7. MQTT X

MQTT X is an open-source client MQTT toolbox for working with an MQTT broker. It is compatible with Windows, Linux, and macOS.

MQTT X features

• Create multiple client connections simultaneously
• Save connection parameters
• Automatically reconnect the client in case of failures
• MQTT payload formatting support
• TCP, SSL/TLS, and WebSocket support
• Automatic subscription to $SYS
• Create a script to simulate data testing
• Convert incoming messages to Base64, JSON, and Hex

MQTT X installation

Visit the official page to select and download the program version you need. Then, run the installation file and follow the instructions to install MQTT X on your system.
You can also download the MQTT X source code from GitHub.

8. MQTT.js

MQTT.js is an open-source client library for the MQTT protocol developers use in Node.js environments and web browsers.

MQTT.js features

• TCP, SSL, TLS, and WebSocket support
• Subscribe/publish features
• Subscribe/publish with username and password
• Provide an error handler that prevents the application from crashing due to unhandled errors
• Reconnect in case of disconnection

MQTT.js installation

You can install MQTT.js using the following command:

npm install mqtt --save

9. Paho MQTT Client Library

The MQTT client library provides robust and reliable functionality that simplifies deploying and implementing MQTT clients.

Eclipse Paho is a project that provides open-source MQTT client libraries for different programming languages such as Python, Go, JavaScript, C/C++, Java, etc.

Paho MQTT Client Library features

• Connect to an MQTT broker
• Publish messages
• Subscribe to topics
• MQTT 3.1/3.1.1/5.0 support
• TCP, SSL/TLS support
• Automatic reconnection to the server when communication is lost.
• Support LWT messages
• Buffer messages while offline and send them when the connection is restored
• Supports WebSockets

Paho MQTT Client Library installation

Paho Python clientYou can download and install the Paho Python client using the pip tool:

pip install paho-mqtt

Paho Java client

To use the Paho Java library, it is enough to include the .jar file, which is available on the project page, in the Java classpath.

Add the following code to the dependencies section to load Paho Java:

<dependency>
     <groupId>org.eclipse.paho</groupId>
     <artifactId>org.eclipse.paho.client.mqttv3</artifactId>
     <version>1.0.2</version>
</dependency>

Paho JavaScript client

Download the Paho JavaScript library from the project page and add it to your HTML file using script tags:

<script src="mqttws31.js">
</script>

10. MQTTInspector

MQTTInspector is a simple and easy-to-use MQTT client made specifically for iOS devices like iPhones and iPads. It allows users to manage MQTT connections, messages, and topics all from the ease of their mobile devices.

MQTTInspector features

• Run on mobile devices
• Provide access to messages, a topic view, and inspect the protocol level
• Filter messages on topic, message content, or MQTT flags
• Store received messages for later review on all detail levels
• Remember favorite broker, subscription, publish, and filter settings
• Configure via http or email configuration file

MQTTInspector installation

MQTTInspector is available for download from the iOS App Store for devices running iOS 8.4 or higher. After installation, users can configure their MQTT broker connections and begin monitoring and publishing messages directly from their iOS devices. 

Alternative for Android users

Currently, no direct equivalent of MQTTInspector is available for Android that does not require a subscription. However, developers can utilize the Eclipse Paho Android Service, an MQTT client library written in Java for Android applications. This library facilitates MQTT integration within Android apps, aligning with other Paho libraries and MQTT.js. 

Choosing the right MQTT tool for your needs

Selecting the right MQTT tool depends on your specific objectives, such as testing connections, monitoring messages, or developing custom applications. Therefore, it’s important to consider the following factors when choosing an MQTT tool:

1. Specific use case

• Testing tools – Both MQTT.fx or MQTT Explorer are excellent for testing MQTT connections or simulating message flows.
• Monitoring and management – To efficiently manage devices and monitor system performance, such as gaining insights into broker metrics, tools like the Management Center for Mosquitto™ provide an intuitive web interface. You can explore the Management Center by signing up for the Cedalo MQTT Platform trial, which also includes access to the Pro Mosquitto broker.

2. Ease of use

Ensure the interface is user-friendly and intuitive, enabling efficient navigation and interaction. Tools with clear dashboards and minimal setup times are preferable.

3. MQTT version compatibility

Confirm that the tool is compatible with multiple versions of the MQTT protocol, including the latest MQTT 5.0, to leverage advanced features like message expiration, topic aliases, and shared subscriptions. 

4. Cross-platform compatibility

Select a tool that matches your needs and ensure it is compatible across various operating systems (e.g., Windows, macOS, Linux) or operates directly via browsers for enhanced convenience. 

5. Broker compatibility

Confirm that the tool integrates smoothly with the MQTT broker you are using. For example, the Management Center for Mosquitto is designed to complement the Pro Mosquitto broker, facilitating efficient management of Pro Mosquitto broker instances and HA clusters.

Focusing on tools that meet your requirements for testing, monitoring, or overseeing your MQTT environment can guarantee a smooth and effective development workflow. 

Conclusion

This article describes the most popular MQTT tools: desktop apps, add-ons for Google Chrome, and client libraries for various programming languages. By reviewing their key features, you can select the best MQTT toolbox that simplifies working with your MQTT broker, enhancing the efficiency of your IoT application.

About the author

Philipp Struss

CEO and Co-Founder of Cedalo

Philipp Struss is a co-founder of Cedalo. He holds a Master's degree in Industrial Engineering and Management, which he earned at the Karlsruhe Institute of Technology (KIT) in Karlsruhe, the Universidad Politécnica de Madrid (UPM) in Madrid, and the University of Cambridge, with a focus on data analytics, manufacturing, and Micro Electro Mechanical Systems (MEMS).

His professional journey includes roles as an analyst in business intelligence at Jedox AG, a process engineer in sensor production at Bosch, and a strategic consultant at McKinsey.

In 2017, he co-founded Cedalo, the company behind Eclipse Mosquitto and Eclipse Streamsheets.