Softwr

Databases · head to head

NATS vs Apache Kafka

NATS logo

NATS

Databases

High-performance messaging system for cloud-native applications

From
Free
Rated
-
Full reviewWebsite
Apache Kafka logo

Apache Kafka

Databases

Open-source distributed event streaming platform

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: NATS core NATS has no persistence at all, so messages are lost if no subscriber is listening; Apache Kafka operationally heavy to self-host: brokers, storage, rebalancing and upgrades are a standing job, which is why managed Kafka is a large market
  • They diverge on capability: NATS covers Very low latency, Apache Kafka covers Durable commit log.

Where they differ

Only the attributes on which NATS and Apache Kafka actually diverge.

Attributes where NATS and Apache Kafka differ
AttributeNATSApache Kafka
Pricing modelOpen source, no licence feeOpen source, no licence fee; managed services billed separately
PlatformsLinux, macOS, Windows, Docker, KubernetesLinux, Windows, macOS, Self-hosted, Docker

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 NATS

  • Very low latency
  • JetStream
  • Single binary
  • Request-reply

Only in Apache Kafka

  • Durable commit log
  • Horizontal scale
  • Kafka Connect
  • Kafka Streams
  • Replication
  • Low latency

What people use each for

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

NATS

  • Service-to-service messaging where latency is the binding constraintnot Apache Kafka
  • Edge and IoT messaging where a lightweight broker mattersnot Apache Kafka
  • Replacing a heavier broker when the workload does not need its guaranteesnot Apache Kafka

Apache Kafka

  • Moving events between services without point-to-point couplingnot NATS
  • Feeding analytics and warehouses from operational systems in near real timenot NATS
  • Replaying history to rebuild state after a consumer bugnot NATS
  • Buffering bursty producers ahead of slower downstream systemsnot NATS

Where each one falls short

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

NATS

  • Core NATS has no persistence at all, so messages are lost if no subscriber is listening
  • JetStream adds the durability but also the operational complexity NATS is chosen to avoid
  • A much smaller ecosystem than Kafka or RabbitMQ, with fewer connectors and integrations
  • Fewer people know it, so hiring and existing organisational knowledge favour the alternatives

Apache Kafka

  • Operationally heavy to self-host: brokers, storage, rebalancing and upgrades are a standing job, which is why managed Kafka is a large market
  • Overkill for straightforward job queues, where a simpler broker is easier to run and reason about
  • Ordering guarantees hold per partition, not per topic, and getting partitioning wrong is a common and expensive design mistake
  • The ecosystem is fragmented across the Apache project and vendor distributions, so documentation and tooling advice often assume a particular distribution

Pricing, plan by plan

NATS

Free
  • NATSFree
    • Full functionality
    • No usage limits
    • Community support

Apache Kafka

Free
  • Apache KafkaFree
    • Full platform
    • Kafka Connect
    • Kafka Streams

Which should you pick?

Choose NATS if

  • You need very low latency.
  • You want to start without paying.
  • You work on Linux, macOS, Windows, Docker, Kubernetes.
  • You also want jetstream.
NATS review

Choose Apache Kafka if

  • You need durable commit log.
  • You want to start without paying.
  • You work on Linux, Windows, macOS, Self-hosted, Docker.
  • You also want horizontal scale.
Apache Kafka review

Questions people ask

Is NATS or Apache Kafka better?
Neither clearly leads. NATS starts at Free and Apache Kafka at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, NATS or Apache Kafka?
NATS starts at Free and Apache Kafka at Free.
Does NATS or Apache Kafka run on more platforms?
NATS runs on Linux, macOS, Windows, Docker, Kubernetes. Apache Kafka runs on Linux, Windows, macOS, Self-hosted, Docker.
Can I use NATS for free?
Both have a free tier, so you can try either at no cost before committing.
What is NATS best used for?
NATS is most often used for service-to-service messaging where latency is the binding constraint, edge and iot messaging where a lightweight broker matters, replacing a heavier broker when the workload does not need its guarantees. Of those, service-to-service messaging where latency is the binding constraint and edge and iot messaging where a lightweight broker matters are not what Apache Kafka is typically brought in for.
What can NATS do that Apache Kafka cannot?
NATS covers Very low latency, JetStream, Single binary, Request-reply. Apache Kafka covers Durable commit log, Horizontal scale, Kafka Connect, Kafka Streams.

Answered from the vendors’ own pages

NATS: Is NATS free?

Yes, open source and CNCF-graduated. Synadia sells a managed service.

Apache Kafka: Is Apache Kafka free?

Yes. Kafka is open source under the Apache License v2 with no licence fee. Costs come from the infrastructure you run it on, or from a managed service such as Confluent Cloud.

NATS: Does NATS persist messages?

Core NATS does not — it is fire-and-forget. JetStream adds persistence, streaming and replay when you need them.

Apache Kafka: How is Kafka different from a message queue?

A queue usually removes a message once it is consumed. Kafka keeps an ordered, durable log, so consumers track their own position and history can be replayed — which is what makes rebuilding state after a bug possible.

NATS: NATS or Kafka?

NATS is far lighter and lower latency, and much simpler to run. Kafka is the answer when you need a durable replayable log and a large connector ecosystem.

Apache Kafka: Who uses Kafka?

The project reports use by more than 80% of the Fortune 100, with over 5 million lifetime downloads.

Apache Kafka: Do I need to run Kafka myself?

No. Self-hosting is the operationally expensive option; managed services such as Confluent Cloud run the brokers for you and bill on throughput and storage instead.

Share

Related pages

More on NATS

More on Apache Kafka

Keep looking

Other head to heads