Kafka Streams: Pricing, Features & Alternatives
Kafka Streams is a client library for building applications and microservices whose input and output live in Kafka. You write ordinary Java or Scala, deploy it like any other service on containers, VMs or bare metal, and scale by running more instances. It supports exactly-once processing semantics and Kafka security, and needs no separate processing cluster. It ships with Apache Kafka (4.4 is the current release) under Apache 2.0.
Who it’s for: Java and Scala teams already on Kafka who want stream processing inside their own services without another cluster.
Category
Stream Processing
Pricing
Free tier available
Free tier
Yes
Best for
Stream Processing: Kafka, microservices, no extra cluster
Kafka Streams at a Glance
- What it is
- Stream processing library for Kafka
- Write jobs in
- Java, Scala
- Licence
- Apache 2.0
- Where it runs
- Inside your own application
- How you pay
- Free
Checked November 2026 against Kafka Streams introduction.
Kafka Streams Pricing Plans (2026)
| Plan | Price |
|---|---|
| Open sourcePopular | $0 (Apache 2.0) |
Pricing summary: Free. Always confirm current pricing on the official site.
Key Kafka Streams Features
- Client library: input and output live in Kafka clusters
- Standard Java and Scala applications; deploy to containers, VMs, bare metal or cloud
- Exactly-once processing semantics
- No separate processing cluster required; scale by running more instances
- Ships with Apache Kafka (4.4) under Apache 2.0
Pros
- +No extra cluster to run
- +Deploys like a normal service
- +Exactly-once with Kafka
- +Free with Kafka
Cons
- −Kafka in and Kafka out only
- −JVM languages only
- −Local state stores need care when rebalancing
Best Kafka Streams Alternatives
Compare allKafka Streams Compared
Kafka Streams FAQ
What is Kafka Streams used for?⌄
Kafka Streams is a stream processing tool. Java and Scala library for stream processing on Kafka topics. No separate cluster: it runs inside your own app. Apache 2.0.
Is Kafka Streams free?⌄
Yes. Kafka Streams has a free tier you can start with, and paid plans for more usage and features.
How much does Kafka Streams cost?⌄
Kafka Streams is free to use.
What are the best Kafka Streams alternatives?⌄
Popular Kafka Streams alternatives include Apache Flink, Materialize, RisingWave. Compare pricing and features on our Kafka Streams alternatives page.
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