Error: DynamoDB Error Message KeyError item is not JSON serializable
Answered by Rafal Wilinski
What's Causing This Error
This error indicates that the JSON module cannot transform the specific item in question into a JSON-formatted string. It can occur when making a typographical error in the list of JSON data you are serializing.
Solution: Here's How To Resolve It
First, check and verify whether there is no syntax error in the specific key and unnecessary punctuation marks are not used. If there is any, it will result in causing a KeyError because the key is unidentified.
Other Common DynamoDB Errors (with Solutions)
- dynamodb condition does not exist
- dynamodb validation error detected
- dynamodb attribute does not exist
- dynamodb system error cloudwatch
- error updating dynamodb table time to live
- dynamodb local could not load credentials from any providers
- dynamodb text contents could not be decoded
- dynamodb unknown error
- DynamoDB is missing the key id in the item
- boto3 dynamodb client error
- DynamoDB VPC endpoint not working
- dynamodb stream missing fields
- moto dynamodb not working
- failed to list tables not authorized dynamodb
- ValidationException: Invalid KeyConditionExpression: Attribute name is a reserved keyword;
Spend less time in the AWS console, use Dynobase.
Try 7-day free trial. No strings attached.
Product Features
DynamoDB Tools
DynamoDB Info
© 2025 Dynobase