Kafka Playground

Interactive visualization of how Apache Kafka works

Mode: Consumer Group Mode | Messages are distributed among group members (each message goes to ONE consumer in the group)
Messages Produced: 0 Partitions: 3 Consumer Groups: 1 Total Consumers: 2
📚 Scenarios:

Producers

Producer
📤
Sends messages to topic
Messages are sent to partitions using a key hash or round-robin.

Topic: orders

📋 Topic "orders"

Consumers

📖 How It Works

Topic = A named feed/channel. Like a database table name. Producers write to it, consumers read from it.

Partition = A topic is split into partitions for parallelism. Each partition is an ordered, immutable log. Messages within a partition keep their order.

Consumer Group = A team of consumers that share the work. Each partition is assigned to exactly ONE consumer in the group. This means each message is processed only once per group.

Without a Group (Standalone) = Each consumer reads ALL partitions independently. Every consumer sees EVERY message. Like a broadcast.

💡 Key insight: With consumer groups, adding more consumers (up to partition count) increases throughput. Beyond that, extra consumers sit idle. Without groups, adding consumers just duplicates processing.