Brokers, storage and cross-AZ transfer — where a Kafka bill really goes.
Broker hours are visible; cross-AZ replication is the hidden majority of a Kafka bill. Model the transfer side on the cross-AZ transfer calculator and the storage on the object storage calculator.
Free managed Kafka cost calculator — brokers, storage and data transfer to your monthly MSK/Confluent bill.
Three things: broker instance hours, storage per GB, and data transfer. On a multi-AZ cluster the cross-zone replication traffic is often the single largest component — frequently more than half of total infrastructure cost — because every message is replicated across availability zones.
Compress messages, use fetch-from-follower to read within a zone, right-size replication, and consider rack-aware or single-AZ topologies where durability requirements allow. Networking, not brokers, is usually the biggest lever.
Cost at different volumes:
| Volume | Monthly | Yearly |
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