Softwr

Databases · head to head

EMQX vs RabbitMQ

EMQX logo

EMQX

Databases

Erlang MQTT broker for large IoT fleets, relicensed to BSL with production free use limited to one node

From
Free
Rated
-
Full reviewWebsite
RabbitMQ logo

RabbitMQ

Databases

Open-source message broker supporting AMQP and other protocols

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: EMQX the move to Business Source Licence 1.1 at version 5.9 in May 2025 limits free production use to a single node, so the clustering that justifies choosing EMQX now requires a paid subscription from the second node onward.; RabbitMQ not built for replay: once consumed, a message is gone, which is exactly what Kafka exists to change
  • They diverge on capability: EMQX covers Erlang clustering, RabbitMQ covers Flexible routing.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which EMQX and RabbitMQ actually diverge.

Attributes where EMQX and RabbitMQ differ
AttributeEMQXRabbitMQ
Pricing modelPer month by connection and session volumeOpen source, no licence fee; managed services billed separately
PlatformsLinux, Docker, Kubernetes, Cloud, macOSLinux, macOS, Windows, Docker, Kubernetes

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated), category (Databases).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in EMQX

  • Erlang clustering
  • MQTT 5.0 and QUIC
  • Rule engine
  • Data integration sinks
  • Session persistence
  • Multi protocol gateways
  • Authentication and authorisation
  • Dashboard and REST API

Only in RabbitMQ

  • Flexible routing
  • Multiple protocols
  • Management UI
  • Clustering and mirroring

What people use each for

The jobs each tool is most often brought in to do.

EMQX

  • A connected vehicle platform needing millions of persistent MQTT sessions with QUIC for handover across mobile networksnot RabbitMQ
  • An industrial operator routing sensor telemetry straight into TimescaleDB or Kafka without writing a consumer servicenot RabbitMQ
  • An IoT product team that has outgrown a single Mosquitto instance and needs clustering and shared subscriptionsnot RabbitMQ
  • A smart building deployment mixing MQTT, CoAP and LwM2M devices on one brokernot RabbitMQ

RabbitMQ

  • Distributing background jobs to a pool of workers with retriesnot EMQX
  • Decoupling services that need delivery rather than a replayable historynot EMQX
  • Routing messages by pattern to different consumers from one publishernot EMQX

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

EMQX

  • The move to Business Source Licence 1.1 at version 5.9 in May 2025 limits free production use to a single node, so the clustering that justifies choosing EMQX now requires a paid subscription from the second node onward.
  • The relicensing arrived in a minor release, which caught users who had pinned to 5.x expecting Apache 2.0 terms and forced legal review of existing deployments.
  • Running an Erlang/OTP cluster well requires operational knowledge most teams do not have, and diagnosing distribution, mnesia or memory issues means learning a runtime you use for nothing else.
  • Enterprise pricing is quoted rather than published for the self-managed edition, so the cost of the clustered configuration you actually need is invisible until you talk to sales.
  • The Serverless tier caps at around a thousand connections and shares infrastructure, which makes it a prototyping tier rather than a genuine small production option.

RabbitMQ

  • Not built for replay: once consumed, a message is gone, which is exactly what Kafka exists to change
  • Throughput ceilings are lower than a log-based platform under very heavy streaming loads
  • Queues that build up degrade broker performance, so consumer lag is an operational problem rather than just a backlog
  • Clustering and partition behaviour has historically been a source of hard-to-diagnose problems

Pricing, plan by plan

EMQX

Free
  • Open Source single nodeFree
    • BSL 1.1 licence since version 5.9
    • Free production use of one node only
    • All former enterprise features visible
  • ServerlessFree
    • Free monthly quota then pay as you go
    • Up to 1,000 connections
    • 8 by 5 support
  • Dedicated Flex$234/month
    • Single tenant cluster
    • Traffic allowance included
    • 24/7 support
  • Enterprise self-managed$undefined/year
    • Deploy on premises, at the edge or in any cloud
    • Clustering licensed
    • 256 MB maximum message size

RabbitMQ

Free
  • RabbitMQFree
    • Full functionality
    • Self-hosted
    • No usage limits

Which should you pick?

Choose EMQX if

  • You need erlang clustering.
  • You want to start without paying.
  • You work on Linux, Docker, Kubernetes, Cloud, macOS.
  • You also want mqtt 5.0 and quic.
EMQX review

Choose RabbitMQ if

  • You need flexible routing.
  • You want to start without paying.
  • You work on Linux, macOS, Windows, Docker, Kubernetes.
  • You also want multiple protocols.
RabbitMQ review

Questions people ask

Is EMQX or RabbitMQ better?
Neither clearly leads. EMQX starts at Free and RabbitMQ at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, EMQX or RabbitMQ?
EMQX starts at Free and RabbitMQ at Free.
Does EMQX or RabbitMQ run on more platforms?
EMQX runs on Linux, Docker, Kubernetes, Cloud, macOS. RabbitMQ runs on Linux, macOS, Windows, Docker, Kubernetes.
Can I use EMQX for free?
Both have a free tier, so you can try either at no cost before committing.
What is EMQX best used for?
EMQX is most often used for a connected vehicle platform needing millions of persistent mqtt sessions with quic for handover across mobile networks, an industrial operator routing sensor telemetry straight into timescaledb or kafka without writing a consumer service, an iot product team that has outgrown a single mosquitto instance and needs clustering and shared subscriptions, a smart building deployment mixing mqtt, coap and lwm2m devices on one broker. Of those, a connected vehicle platform needing millions of persistent mqtt sessions with quic for handover across mobile networks and an industrial operator routing sensor telemetry straight into timescaledb or kafka without writing a consumer service are not what RabbitMQ is typically brought in for.
What can EMQX do that RabbitMQ cannot?
EMQX covers Erlang clustering, MQTT 5.0 and QUIC, Rule engine, Data integration sinks. RabbitMQ covers Flexible routing, Multiple protocols, Management UI, Clustering and mirroring.

Answered from the vendors’ own pages

EMQX: Is EMQX still open source?

Not in the OSI sense since version 5.9. It is source-available under Business Source Licence 1.1, reverting to Apache 2.0 four years after each release.

RabbitMQ: Is RabbitMQ free?

Yes, open source with no licence fee. Broadcom sells commercial support.

EMQX: Can I run a free cluster?

No. The additional use grant permits free production use of one node; clustering requires a commercial licence.

RabbitMQ: RabbitMQ or Kafka?

RabbitMQ is a message broker: simpler to run and better at flexible routing and work queues. Kafka is a replayable event log built for very high throughput streaming, and much heavier to operate.

EMQX: What changed for existing users?

Community and enterprise editions merged, so all features are now visible, but the licence terms tightened in the same minor release.

RabbitMQ: Can RabbitMQ replay messages?

Not in the way Kafka can. Messages are removed once acknowledged, so rebuilding state from history is not the model.

EMQX: Which version is still Apache 2.0?

Releases before 5.9 remain under Apache 2.0, and each BSL release converts to Apache 2.0 four years after publication.

Share

Related pages

More on EMQX

More on RabbitMQ

Keep looking

Other head to heads