EMQX

EMQX is an MQTT messaging platform for teams connecting fleets of devices and processing their data in real time. It is strongest for IoT deployments that need multiple protocols, integrated data flows, and a choice of managed or self-hosted operation. The free Serverless plan is useful for a small start, but its connection, throughput, and message-size limits make plan selection important as workloads grow.

Overview

EMQX Enterprise combines MQTT publish/subscribe messaging with durable message queuing, giving teams one platform for live device traffic and queued messages. EMQX says a cluster can handle up to 100 million concurrent MQTT connections—a scale ceiling relevant to large fleets, not a reason by itself to choose the platform for a smaller rollout. Configurable delivery guarantees let teams set message handling to fit their workload.

Deployment can be self-managed with Docker, a Kubernetes Operator, or installation packages, or managed through cloud offerings. The HTTP management API follows OpenAPI 3.0, a useful fit for teams automating administration. EMQX launched as a project in 2013; its maker, EMQ, was founded in 2017.

Key features

MQTT is joined by MQTT-SN, STOMP, CoAP, LwM2M, OCPP, GB/T 32960, JT/T 808, and NATS, with gateways and protocols also including QUIC. That breadth can reduce the need for separate brokers across a mixed device estate, though teams should confirm that their specific devices and integrations fit the supported set.

The SQL-based Rule Engine and visual Flow Designer support filtering, transformation, enrichment, and routing. More than 50 native integrations include Kafka, PostgreSQL, MongoDB, AWS, Azure, OpenAI, Anthropic, and Google Gemini. These capabilities suit pipelines that need to move device data into databases, cloud services, or other systems without treating the broker as a simple pass-through.

Security features include TLS/mTLS, X.509 certificate authentication, access controls, and audit logs. EMQ’s trust center describes ISO/IEC 27001:2022 and TISAX certifications and says SOC 2 Type 1 reports are available for EMQX Cloud and EMQX Enterprise—relevant credentials for organizations with compliance requirements.

Pricing

EMQX uses a freemium model, with paid plans from $234/mo and a 14-day trial on Dedicated Flex. The main trade-off is between a capped usage-based starting point, a dedicated cloud deployment, and custom-priced options for greater control or scale.

Serverless: free, billed $0 / Month, with usage-based charges beyond the monthly free quota. It includes up to 1,000 connections, free monthly quotas for sessions, traffic, and rule actions, TLS/SSL, and 8/5 support. The comparison caps this plan at 1,000 sessions, 1,000 TPS, and a 1 MB message size. It is a practical entry point, but those ceilings constrain larger or busier workloads.

Dedicated Flex: $234 a month, starting at $234 / Month. It provides a single-tenant dedicated VPC, 40+ integrations, a 99.99% uptime SLA, 24/7 premium support, and a 14-day trial. This is the clearest step up for teams that need dedicated infrastructure and round-the-clock support.

BYOC: Custom pricing. It runs in your VPC and includes managed upgrades, observability, and tailored compliance, fitting organizations that need their cloud environment and compliance needs accommodated.

Enterprise: Custom pricing, with unlimited sessions, unlimited TPS, and a 256 MB message size. It is the relevant option when Serverless limits are insufficient, though it does not have a published price.

Platforms

EMQX lists API, Linux, macOS, self-hosted, and web support. Docker, the Kubernetes Operator, and installation packages support self-managed deployment; listed package platforms include macOS and Linux distributions. That range offers operational flexibility, but teams should choose a plan based on whether they want to manage deployment themselves or use a managed cloud option.

Who it's for

EMQX is best suited to IoT teams that need MQTT at scale alongside message queuing, data processing, broad protocol support, and downstream integrations. Serverless offers a way to begin without a plan charge, while Dedicated Flex and the custom-priced plans serve deployments needing dedicated infrastructure, higher limits, or a customer-controlled VPC. It is a less natural fit for a small, simple broker requirement if the Serverless caps are restrictive or the wider platform is unnecessary.

Pros and cons

Pro: Messaging, durable queues, data rules, and integrations sit in one platform, reducing the need to assemble those functions separately.

Pro: Protocol breadth and deployment choices accommodate varied device estates and operational preferences.

Pro: Dedicated Flex includes a 99.99% uptime SLA and 24/7 support, while security features and stated certifications address enterprise requirements.

Con: Serverless has explicit caps of 1,000 sessions, 1,000 TPS, and 1 MB per message, so growing workloads may need a paid plan.

Con: BYOC and Enterprise use custom pricing, making cost comparison less direct than with the free and Dedicated Flex plans.

Alternatives

HiveMQ MQTT Broker is another freemium MQTT option; its Lab plan has 100 connections and 100 msgs/sec based on a normalized 5 KB message size, while Launch costs $299 a month. It is worth comparing when those plan terms better fit the intended workload.

Confluent Cloud is a freemium alternative with a free Basic plan, serverless managed Kafka clusters, autoscaling Kafka resources, and more than 80 fully managed connectors. Choose it when managed Kafka and its connector ecosystem are a closer match than MQTT-centered IoT messaging.

Aiven for Apache Kafka offers a free plan capped at 250 KiB/s throughput, three days of retention, five topics, and two partitions per topic, plus a Developer plan at $35 a month. It is a relevant alternative when Apache Kafka is the target platform and those entry-tier limits suit the workload.

Google Cloud Pub/Sub provides a free usage allowance of 10 GiB throughput and a pay-as-you-go throughput plan priced at $40 a month after the first 10 GiB per calendar month. Consider it when that throughput-based model is a better fit than EMQX’s MQTT and IoT focus.

Solace PubSub+ Event Broker is another freemium event-broker option, with a 30-day cloud event broker trial. It merits consideration when comparing event-broker options.

RabbitMQ is a free, self-managed open-source broker under the Mozilla Public License 2.0, with community-based best-effort support. It suits teams prioritizing a no-cost self-managed broker and comfortable relying on community support.

Apache Pulsar is a free open-source distribution from the Apache Software Foundation. It is an alternative for teams seeking that open-source option.

Eclipse Mosquitto is a free, on-premises option focused on core MQTT features. It is the simpler comparison for teams that need basic MQTT rather than EMQX’s broader data-processing and integration capabilities.

For broader comparisons, browse Message Queue (MQ) Software and Message Broker Software.

Verdict

Choose EMQX when an IoT deployment needs MQTT messaging plus data processing, integrations, and flexible deployment in one platform. Its strongest case is breadth that can carry from a small Serverless start to dedicated or custom enterprise deployments. Look elsewhere if a capped free tier is not enough and the paid or custom-priced options do not suit the budget, or if a simpler broker meets the requirement.