Free tools Windows power users keep installed
One-click scans. No signup required.
For a lightweight MQTT deployment, Eclipse Mosquitto is a sensible place to start. HiveMQ Community Edition is an option when its Java-based deployment suits your environment; EMQX is worth comparing when you need additional IoT protocols, but check the license for your exact version—EMQX 5.9.0 and later requires a license file for clusters with more than one node. There is no universal best broker: match protocol support, operations, licensing and deployment demands to your workload, then test under representative conditions.
What an MQTT broker does
MQTT is a lightweight publish/subscribe messaging protocol: clients publish messages to a broker, which routes them to clients subscribed to the relevant topics. That model is commonly used for IoT devices, sensors and embedded systems. The broker is the central service, so its protocol support and operating characteristics affect every connected client.
| # | Preview | Product | Price | |
|---|---|---|---|---|
| 1 |
|
Node RED and MQTT for IoT Projects: Build Visual Automation Workflows, Connect ESP32 Devices,... | $17.28 | Buy on Amazon |
As an Amazon Associate I earn from qualifying purchases.
All three leading options below implement MQTT 5.0 as well as earlier MQTT versions, but they differ in runtime, license, and the surrounding protocols or operational features to evaluate.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errorsCompare the main open-source MQTT brokers
| Broker | Documented MQTT and transport support | License and runtime notes | Best starting point when |
|---|---|---|---|
| Eclipse Mosquitto | MQTT 5.0, 3.1.1 and 3.1; includes C client library and command-line clients | Project describes Mosquitto as EPL/EDL licensed | You want a lightweight broker for a small server, single-board computer, or embedded deployment |
| HiveMQ Community Edition | MQTT 3.1, 3.1.1 and 5.0; TCP, TLS, WebSocket and secure WebSocket | Apache 2.0; Java 11 minimum, with Linux recommended by the repository | A Java-based broker and its documented transport options fit your environment |
| EMQX | MQTT 3.1, 3.1.1 and 5.0; also documents MQTT-SN, CoAP, LwM2M and MQTT over QUIC | From version 5.9.0, repository states BSL 1.1 applies; clusters of more than one node require a license file | You need to assess additional IoT protocols, while checking the exact release and license terms |
These are documented distinctions, not a ranking by throughput or ease of operation. Consult each project’s current documentation for requirements such as persistence, offline-session behavior, authentication, authorization, observability, supported platforms and upgrade procedures.
#1 Best Overall
When Mosquitto is the practical choice
The Mosquitto project describes its broker as suitable for deployments ranging from low-power sensors and microcontrollers to full servers. Its relatively lightweight positioning makes it a straightforward starting point for learning MQTT, self-hosting, or an edge installation where a modest footprint matters. The project also supplies a C client library and the mosquitto_pub and mosquitto_sub command-line tools, useful for checking basic publishing and subscriptions.
Mosquitto’s open-source project is distinct from Cedalo’s commercial Pro Mosquitto edition. The project site identifies Pro as a separately licensed offering with features including high availability, integrations, REST APIs, persistent queuing and dedicated support. If one of those capabilities is essential, check the current product and licensing details rather than assuming it is part of the open-source broker.
When HiveMQ Community Edition fits
HiveMQ CE supports MQTT 3.x and MQTT 5, with TCP, TLS, WebSocket and secure WebSocket transports. Its Apache 2.0 license may suit projects that need that license, but its Java runtime requirement is a real deployment consideration: the repository specifies Java 11 as the minimum and recommends Linux.
The project documents running CE from a binary package or Docker image. For remote clients, ensure the broker is reachable over the network and the necessary firewall ports are open. Confirm in current CE documentation that its capabilities meet your requirements; do not assume a feature of a commercial HiveMQ product is available in Community Edition.
What to check before choosing EMQX
EMQX documents support for MQTT 3.1, 3.1.1 and 5.0, plus additional IoT protocols such as MQTT-SN, CoAP and LwM2M, and MQTT over QUIC. Those options may matter when devices or services need protocols beyond standard MQTT.
Licensing depends on the release. The EMQX repository states that starting with version 5.9.0, EMQX adopted the Business Source License 1.1, and a cluster of more than one node requires a license file. Verify the license terms for the exact version and deployment you intend to run, especially before designing a multi-node cluster. The repository documents single-node Docker startup and points Kubernetes cluster deployments to its operator documentation.
How to evaluate smaller broker projects
NanoMQ and FlashMQ are also listed in the MQTT.org broker directory. A directory entry is useful for discovering candidates, but is not enough to establish current capabilities or suitability. Check the project’s own documentation for the current MQTT versions, license, supported platforms, maintenance activity and support model before selecting either for a real deployment.
Choose by workload, not by a headline benchmark
Before committing, check the requirements that affect your installation and its failure modes:
- Protocol and transport: Confirm the MQTT versions and connection methods required by every client. If you need other IoT protocols, verify that the broker supports them directly or through a documented integration.
- Availability and recovery: Determine whether one broker is acceptable or whether you need clustering and failover. Check release-specific license conditions before relying on a clustered design.
- Delivery behavior: Review persistence, offline-session handling and queuing against what happens when clients or the broker disconnect.
- Security: Verify authentication, authorization, encryption and network exposure in the current documentation; do not treat TLS support alone as a complete security plan.
- Operations: Compare footprint, CPU and operating-system support, observability, upgrade path, maintenance burden and available support.
- License fit: Read the license for the exact project version and deployment model, including commercial or multi-node use where relevant.
Then test finalists using the client count, payload sizes, connection patterns and network conditions you expect in production. Measure the results that matter to your application, including delivery behavior and recovery, not just a single throughput number.
How to interpret published performance figures
A 2023 study by Jasenka Dizdarevic, Marc Michalke and Admela Jukan compared implementations using three virtual machines and three Raspberry Pi devices under different network conditions. Across the implementations in that test, reported median response times were about 4.8–8 ms in the local virtual-machine scenario, 8–13 ms in the optimal-network scenario, and 11–18 ms in the worst-network scenario. These figures describe that study’s hardware and test conditions; they are not specifications for a broker or predictions for another deployment.
The study’s results reinforce why a benchmark is only useful when its hardware, message size, latency, packet loss and jitter resemble your own conditions. Use published results to understand testing methods, then benchmark your shortlisted broker on representative hardware and network links.
Quick Recap
Project references
- Eclipse Mosquitto project
- HiveMQ Community Edition repository
- EMQX repository
- MQTT.org software directory
- 2023 MQTT broker performance study
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
