What is the maximum number of messages Kafka can store in its queue?

Apache Kafka does not directly limit the maximum number of messages in a queue (topic). Instead, the number of messages depends on available disk space and data retention settings. Messages are stored in logs on disk, and Kafka allows configuring retention time (e.g., 7 days) or maximum log size. Therefore, theoretically, Kafka can store a very large number of messages, limited only by server resources and retention policies.