Use the AWS Cost report to analyze cost data found in your AWS Cost & Usage Report across all of your consolidated or linked AWS accounts. This report provides a breakdown of your costs for EC2, RDS, and S3 resources. The AWS Cost report is generated daily after initial setup.
This report is an ideal place to start your right sizing planning because it allows you to quickly understand your infrastructure spend on an operational level, such as identifying an over-reliance on On-Demand resources used for predictable, long-term workloads (more suited for reservations and savings plans) or those that might be less critical and time sensitive (more suited for Spot instances).
Cost reports enable you to easily identify expensive instances and compare them against utilization, type, elements, and tags. These multi-dimensional reports also break down information like total versus individual instance costs and even how much each instance state (Reserved, On-Demand) costs. Custom tagging is another easy way to group your instances.
Cost Reports are generated once per week. It may take up to 7 days before your first report is available.
There are three groups of S3 metrics: Daily storage metrics for buckets, Request metrics, and Replication metrics. The first group includes two metrics: Bucket Size Bytes and Number of Objects. These metrics are free of charge and reported by AWS once daily.
The other metrics are billed additionally by AWS. You can opt in for request metrics through the Management tab of the S3 configuration in the AWS console.