checksumAlgorithm

Indicates the algorithm used to create the checksum for the request when you use the SDK. This header will not provide any additional functionality if you don't use the SDK. When you send this header, there must be a corresponding x-amz-checksum or x-amz-trailer header sent. Otherwise, Amazon S3 fails the request with the HTTP status code 400 Bad Request. For more information, see Checking object integrity in the Amazon S3 User Guide.

If you provide an individual checksum, Amazon S3 ignores any provided ChecksumAlgorithm parameter.

For directory buckets, when you use Amazon Web Services SDKs, CRC32 is the default checksum algorithm that's used for performance.