With the rapid development of the IoT industry, the MQTT protocol is being used by more and more companies and developers. In the process of learning and using MQTT, a handy client tool can greatly facilitate developers to explore MQTT features and debug IoT applications, shortening the development cycle.

There is a wide variety of MQTT client tools with different functional focuses. For beginners and even MQTT experts, it is a challenge to choose a suitable MQTT client tool.

We have selected the latest and most useful 7 MQTT client tools as of 2022 and listed them by desktop, browser, and command line. We hope this article will help MQTT developers quickly find a suitable client tool for MQTT testing.

How to choose an MQTT client?

MQTT client tools are commonly used to establish connections to MQTT brokers for subscription, message sending and receiving operations. A good MQTT client tool should have the following features.

• Support for one-way and two-way SSL authentication.
• Support for MQTT 5 features.
• Maintain ease of use on a full-featured basis.
• Support for multiple clients online at the same time.
• Cross-platform, available under different operating systems.
• Support MQTT over WebSocket.
• Advanced features: Customized script, logging, payload format conversion, etc.

MQTT desktop client

MQTT X

MQTT X is a cross-platform MQTT 5.0 client tool open sourced by EMQ, which can run on macOS, Linux and Windows, and supports formatting MQTT payload.

It simplifies test operation with the help of a familiar, chat-like interface. It’s easy and quick to create multiple, simultaneous online MQTT client connections, and can test the connection, publishing, and subscription functions of MQTT/TCP, MQTT/TLS, MQTT/WebSocket as well as other MQTT protocol features.

MQTT X is dedicated to building an elegant, easy-to-use, full-platform MQTT client, and has recently released both MQTT X CLI and MQTT X Web. Now, MQTT X has reached 2K on GitHub Star and is loved by more and more developers.

Features

• Cross-platform for Windows, macOS, Linux
• Support MQTT v3.1.1 and MQTT v5.0 protocols
• Support CA, self-signed certificate, and single and two-way SSL /TLS authentication
• Support theme switching between Light, Dark and Night
• Support MQTT over WebSocket
• Support Hex, Base64, JSON, Plaintext
• Support English, Japanese, Simplified Chinese, Turkish and Hungarian
• Support custom color marking when subscribing to topics
• Support for automatic subscription to $SYS and view bytes statistics
• Customizable script to simulate data testing
• Full logging capabilities

Download

Website: https://mqttx.app/

GitHub: https://github.com/emqx/MQTTX/releases

MQTT Explorer

MQTT Explorer is a comprehensive MQTT client that provides a structured overview of your MQTT topics and makes working with devices/services on your broker dead-simple.

MQTT Explorer supports difference comparison and visual chart display of received payload messages. Similar to MQTT.fx, MQTT Explorer can only create a single connection and cannot have multiple clients online at the same time.

Features

• Visualize topics and dynamic preview of the change of topic
• Delete the retained topics
• Search/filter topics
• Recursive delete topics
• Difference view of current and previously received messages
• Publish topics
• Draw digital topics
• Retain the historic record of every topic
• Dark/Light topic

Download

https://github.com/thomasnordquist/MQTT-Explorer

MQTT.fx

MQTT.fx was developed by Jens Deters. Since January 2021 MQTT.fx has moved to Softblade - a new founded German company now taking care about further development of MQTT.fx, and released the commercial version MQTT.fx® 5.0. The MQTT.fx described in this article is the free 1.x version.

MQTT.fx is developed with JavaFX, supports saving multiple connection configurations, multiple types of encryption methods, specifies multiple types of certificates, and can set an HTTP proxy server when creating a connection.

In general, MQTT.fx has rich and mature functions and supports many configuration items in TCP connections, but users can only establish one connection at a time. In addition, it does not implement support for WebSocket and cannot be used in the test scenario of MQTT over WebSocket.

Features

• Predefine message template
• Get the status of the broker through the system topic $SYS
• Support for JavaScript scripts through Nashorn Engine
• Support log display, display log information in the connection
• Cross-platform desktop with support for Windows, macOS, and Linux

Download

https://www.jensd.de/wordpress/?p=2746

MQTT online client

MQTT X Web

MQTT X Web is an open source MQTT 5.0 browser client and an online MQTT WebSocket client tool. Developers can use WebSockets to quickly connect to MQTT servers in the browser and debug MQTT services and applications faster without installing MQTT X.

Try now：http://www.emqx.io/online-mqtt-client

For more information, please check out: https://github.com/emqx/MQTTX/tree/main/web

MQTT CLI

MQTT X CLI

MQTT X CLI is a fully open source MQTT 5.0 command line client tool, i.e., MQTT X on the command line. This allows developers to develop and debug MQTT services and applications faster using the command line without the graphical interface.

Features

• Dependency-free: Get up and run with no prerequisites required

• Easy to Integrate: Quick integration into automation test scripts

• One and Two Way SSL: Support for one-way and two-way SSL authentication

Download

The MQTT X CLI can be quickly downloaded and installed on macOS, Linux, and Windows systems without any environmental dependencies, simply by executing commands in a terminal.

Try Now: https://mqttx.app/cli

Usage

Connect

mqttx conn -h 'broker.emqx.io' -p 1883 -u 'admin' -P 'public'

Subscribe

mqttx sub -t 'hello' -h 'broker.emqx.io' -p 1883

Publish

mqttx pub -t 'hello' -h 'broker.emqx.io' -p 1883 -m 'from MQTTX CLI'

Publishing multiple messages

mqttx pub -t 'mqttx/cli' -h 'broker.emqx.io' -p 1883 -s -M

The MQTT X CLI also supports a pub command to publish multiple messages, just add a -M parameter and a -s parameter to the command in the editor, and newline it after each entry.

NanoMQ CLI

NanoMQ is an ultra-lightweight and blazing-fast MQTT broker for IoT edge, which contains an abundant toolkit including broker, bench, conn, pub, sub client.

Features

• Support performance testing
• Support MQTT 5.0
• Ability to run on edge devices
• Support reading file content as payload

Download

https://nanomq.io/downloads

Usage

MQTT performance testing tool

# Start 10 connections and send 100 Qos0 messages to the topic t every second, 
# where the size of each message payload is 16 bytes
nanomq_cli bench pub -t t -h broker.emqx.io -s 16 -q 0 -c 10 -I 10

# Start 500 connections, and each subscribes to the t topic with Qos0
nanomq_cli bench sub -t t -h broker.emqx.io -c 500

# Start 100 connections
nanomq_cli bench conn -h broker.emqx.io -c 100

MQTT client

# Send 100 Qos2 messages test to the topic t
nanomq_cli pub -t t -h broker.emqx.io -q 2 -L 100 -m test

# Subscribe
nanomq_cli sub -t t -h broker.emqx.io -q 1

Mosquitto CLI

Mosquitto is an open source implementation of a server for versions 5.0, 3.1.1, and 3.1 of the MQTT protocol. It also includes a C and C++ client library, and the mosquitto_pub and mosquitto_sub utilities for publishing and subscribing.

Mosquitto CLI has multiple configuration options, supports connections through TLS certificate and a proxy server, supports debug mode, and can get more detailed message information in debug mode.

Features

• Thie lightweight command-line tool, support debug mode
• Support encrypted and nonencrypted connecting to MQTT broker
• Easy to test in the remote server

Download

https://github.com/eclipse/mosquitto

Usage

Subscribe

mosquitto_sub -t 'test/topic' -v

Publish

mosquitto_pub -t 'test/topic' -m 'hello world'