dto fee is free?

Hi,

No, it is not free. As described on the AWS documentation, you pay for all bandwidth into and out of Amazon S3, except for the following:

• Data transferred out to the internet for the first 100GB per month, aggregated across all AWS Services and Regions (except China and GovCloud)
• Data transferred in from the internet.
• Data transferred between S3 buckets in the same AWS Region.
• Data transferred from an Amazon S3 bucket to any AWS service(s) within the same AWS Region as the S3 bucket (including to a different account in the same AWS Region).
• Data transferred out to Amazon CloudFront (CloudFront).