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Networking · head to head

Eclipse Mosquitto vs VictoriaMetrics

Eclipse Mosquitto logo

Eclipse Mosquitto

Networking

Small, EPL-licensed MQTT broker that runs on hardware other brokers cannot

From
Free
Rated
-
Full reviewWebsite
VictoriaMetrics logo

VictoriaMetrics

Cloud

Fast, cost-effective time series database for metrics

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Eclipse Mosquitto there is no clustering: Mosquitto is a single process, so high availability means building your own failover and accepting session loss on switchover.; VictoriaMetrics promQL compatibility is very close but not identical, and MetricsQL extensions do not port back
  • They diverge on capability: Eclipse Mosquitto covers MQTT 5.0 support, VictoriaMetrics covers PromQL compatible.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Eclipse Mosquitto and VictoriaMetrics actually diverge.

Attributes where Eclipse Mosquitto and VictoriaMetrics differ
AttributeEclipse MosquittoVictoriaMetrics
PlatformsLinux, Windows, macOS, DockerLinux, Docker, Kubernetes, Self-hosted
CategoryNetworkingCloud

Identical on both: starting price (Free), pricing model (Open source, no licence fee), free tier (Yes), user rating (Not yet rated).

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 Eclipse Mosquitto

  • MQTT 5.0 support
  • Very small footprint
  • Bridging
  • WebSockets listener
  • Command line clients
  • Dynamic security plugin

Only in VictoriaMetrics

  • PromQL compatible
  • Low resource use
  • Single binary or cluster
  • Remote write target

What people use each for

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

Eclipse Mosquitto

  • A home or building automation stack where the broker must run on the same small computer as everything elsenot VictoriaMetrics
  • An industrial gateway that buffers local telemetry and bridges selected topics to a cloud brokernot VictoriaMetrics
  • Local development and testing of MQTT clients without provisioning a cloud IoT servicenot VictoriaMetrics
  • An air-gapped deployment where a broker with no licence server and no phone-home behaviour is a requirementnot VictoriaMetrics

VictoriaMetrics

  • Keeping months or years of Prometheus metrics without the memory costnot Eclipse Mosquitto
  • High-cardinality metrics where Prometheus strugglesnot Eclipse Mosquitto
  • Consolidating metrics from many Prometheus instances into one queryable storenot Eclipse Mosquitto

Where each one falls short

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

Eclipse Mosquitto

  • There is no clustering: Mosquitto is a single process, so high availability means building your own failover and accepting session loss on switchover.
  • Persistence is a local file rather than a replicated store, so a disk failure or an unclean shutdown can lose retained messages and queued QoS traffic.
  • Practical capacity is a few thousand concurrent clients on typical hardware, so a growing device fleet eventually forces a migration to a clustered broker.
  • The Eclipse Public Licence is weak copyleft rather than permissive, which some legal teams treat as a blocker when embedding the broker in a shipped commercial product.
  • There is no commercial support to buy from the project, so production incidents rely on community mailing lists or on paying a third party who happens to know the codebase.

VictoriaMetrics

  • PromQL compatibility is very close but not identical, and MetricsQL extensions do not port back
  • Smaller community than Prometheus, so fewer guides and third-party integrations
  • The clustered version has meaningfully more moving parts than the single binary suggests
  • Some enterprise features sit outside the open-source offering

Pricing, plan by plan

Eclipse Mosquitto

Free
  • Eclipse MosquittoFree
    • Eclipse Public License 2.0 with Eclipse Distribution Licence
    • MQTT 5.0, 3.1.1 and 3.1
    • No client or message limits beyond your hardware

VictoriaMetrics

Free
  • VictoriaMetricsFree
    • Full functionality
    • No data limits
    • Community support

Which should you pick?

Choose Eclipse Mosquitto if

  • You need mqtt 5.0 support.
  • You want to start without paying.
  • You work on Linux, Windows, macOS, Docker.
  • You also want very small footprint.
Eclipse Mosquitto review

Choose VictoriaMetrics if

  • You need promql compatible.
  • You want to start without paying.
  • You work on Linux, Docker, Kubernetes, Self-hosted.
  • You also want low resource use.
VictoriaMetrics review

Questions people ask

Is Eclipse Mosquitto or VictoriaMetrics better?
Neither clearly leads. Eclipse Mosquitto starts at Free and VictoriaMetrics at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Eclipse Mosquitto or VictoriaMetrics?
Eclipse Mosquitto starts at Free and VictoriaMetrics at Free.
Does Eclipse Mosquitto or VictoriaMetrics run on more platforms?
Eclipse Mosquitto runs on Linux, Windows, macOS, Docker. VictoriaMetrics runs on Linux, Docker, Kubernetes, Self-hosted.
Can I use Eclipse Mosquitto for free?
Both have a free tier, so you can try either at no cost before committing.
What is Eclipse Mosquitto best used for?
Eclipse Mosquitto is most often used for a home or building automation stack where the broker must run on the same small computer as everything else, an industrial gateway that buffers local telemetry and bridges selected topics to a cloud broker, local development and testing of mqtt clients without provisioning a cloud iot service, an air-gapped deployment where a broker with no licence server and no phone-home behaviour is a requirement. Of those, a home or building automation stack where the broker must run on the same small computer as everything else and an industrial gateway that buffers local telemetry and bridges selected topics to a cloud broker are not what VictoriaMetrics is typically brought in for.
What can Eclipse Mosquitto do that VictoriaMetrics cannot?
Eclipse Mosquitto covers MQTT 5.0 support, Very small footprint, Bridging, WebSockets listener. VictoriaMetrics covers PromQL compatible, Low resource use, Single binary or cluster, Remote write target.

Answered from the vendors’ own pages

Eclipse Mosquitto: Can Mosquitto be clustered?

No. It is a single process. High availability requires an external failover arrangement you build yourself.

VictoriaMetrics: Is VictoriaMetrics free?

The open-source version is free with no data limits. An enterprise edition and cloud service are paid.

Eclipse Mosquitto: What licence is it?

Eclipse Public License 2.0 alongside the Eclipse Distribution License, a weak copyleft rather than a permissive licence.

VictoriaMetrics: Does it replace Prometheus?

It can, but most teams keep Prometheus for scraping and use VictoriaMetrics as the long-term store behind it.

Eclipse Mosquitto: How many clients can it handle?

A few thousand concurrent connections on ordinary hardware; beyond that, use a clustered broker.

VictoriaMetrics: Is PromQL fully supported?

Very nearly. It implements PromQL and extends it with MetricsQL, though a small number of edge-case behaviours differ.

Eclipse Mosquitto: Does it support MQTT 5?

Yes, along with 3.1.1 and 3.1.

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