What is the maximum size of messages in SQS?

The maximum size of message in SQS IS 256 KB.

The correct answer to the maximum size of messages in Amazon Simple Queue Service (SQS) is 256 KB (kilobytes). SQS supports messages up to this size, including both message body and any message attributes. If you need to send larger messages, you might want to consider using Amazon Simple Notification Service (SNS) or Amazon Kinesis Data Streams, which can handle larger payloads.