# Cluster Sizes

IONOS Cloud Event Streams for Apache Kafka offers a range of cluster sizes to meet the diverse needs of different applications, from development and testing environments to large-scale production deployments. Each cluster size is designed with specific hardware configurations to provide the right balance of performance, capacity, and cost-efficiency.

{% hint style="info" %}
**Note:**

* Select the size of your Kafka cluster according to your throughput and data retention requirements.
* For example, if you have three topics, each with a retention time of seven days, and you expect 500 KB of data per second on each of these topics, you can calculate that you will need a minimum of 866 GB of total storage in your Kafka cluster.
* Consider that the final storage consumption can be several times the incoming data volume, depending on the configured replication factor for the topic.
  {% endhint %}

## Cluster Size Options

### XS Cluster

* **Broker Count**: 3
* **Cores per Broker**: 1
* **RAM per Kafka Broker**: 2 GB
* **Storage per Broker**: 195 GB
* **Total Storage**: 585 GB

The XS cluster is ideal for development, testing, and small-scale applications that require a modest amount of resources. It provides sufficient capacity to handle light workloads while maintaining cost efficiency.

### S Cluster

* **Broker Count**: 3
* **Cores per Broker**: 2
* **RAM per Kafka Broker**: 4 GB
* **Storage per Broker**: 250 GB
* **Total Storage**: 750 GB

The S cluster is suitable for small to medium-sized applications that need moderate resources. It offers enhanced performance and storage capacity compared to the XS cluster, making it a good choice for applications with higher throughput and storage requirements.

### M Cluster

* **Broker Count**: 3
* **Cores per Broker**: 2
* **RAM per Kafka Broker**: 8 GB
* **Storage per Broker**: 400 GB
* **Total Storage**: 1200 GB

The M cluster is designed for medium-sized applications that demand higher performance and greater storage capacity. It provides a balanced configuration that can handle increased data volumes and more intensive processing tasks.

### L Cluster

* **Broker Count**: 3
* **Cores per Broker**: 4
* **RAM per Kafka Broker**: 16 GB
* **Storage per Broker**: 800 GB
* **Total Storage**: 2400 GB

The L cluster is well-suited for large applications with high throughput and substantial storage needs. With more cores and RAM per broker, this cluster size delivers superior performance and can support more demanding workloads.

### XL Cluster

* **Broker Count**: 3
* **Cores per Broker**: 8
* **RAM per Kafka Broker**: 32 GB
* **Storage per Broker**: 1500 GB
* **Total Storage**: 4500 GB

The XL cluster is designed for enterprise-level applications and extremely high-throughput environments. It offers the highest performance and storage capacity, ensuring that even the most demanding applications can run smoothly and efficiently.