For RabbitMQ version 4.0+ the default max message size has been updated to 16mb. The new maximum has been reduced from 2gb to 536mb. For versions 3.13.X and older the default message size is 128mb. We don’t recommend sending messages larger than 128mb.
If you need to adjust your max_message size you can do so from the CloudAMQP console ➡️ RabbitMQ ➡️ Configuration ➡️
rabbit.max_message_size.
It is recommended to set the value closer to your average message size.
LavinMQ
For LavinMQ max message size is 128mb. Max message is configurable.
This article was last updated September 2025.
References:
https://github.com/rabbitmq/rabbitmq-server/issues/147#issuecomment-470882099
https://github.com/rabbitmq/rabbitmq-common/pull/289
https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.0.1
https://lavinmq.com/blog/lavinmq-adds-support-for-max-message-size
