What is the maximum size of an item that can be stored in DynamoDB?

The maximum size of an item that can be stored in DynamoDB is indeed 400 KB. This limitation applies to the entire item, including all of its attributes. An item in DynamoDB consists of a unique primary key and an attribute-value map. Given that DynamoDB is designed for high-speed operations, the limit on item size helps ensure performance efficiency.

Understanding this limit is crucial when designing applications that utilize DynamoDB as it impacts how you structure your data. If an item exceeds this size, it would need to be split into multiple items or structured differently to comply with DynamoDB's constraints.

Other sizes mentioned do not reflect the current limits imposed by DynamoDB for storing items, and knowing the correct limit helps in optimal data modeling and application performance.