Posted On: Feb 5, 2019

AWS Cost Explorer allows you to visualize and monitor your reservations both at a high level (e.g., cost savings associated with all Amazon EC2 reservations) or for highly-specific requests (e.g., reservation utilization associated with all regional Amazon EC2 reservations owned by a particular linked account). Starting today, you can access information about the normalized units associated with your reservations in AWS Cost Explorer, making it easier to understand how your reservations (including Size Flexible RIs) are applied to your instance usage.

Reservations offer you a discounted hourly rate (up to 75%) compared to on-demand usage in exchange for committing to a one- or three-year term of service usage. Each reservation has an instance size footprint, which is determined by the normalization factor of the instance type and the number of instances in the reservation. To calculate the instance size footprint of a Reserved Instance, you can multiply the number of instances by the normalization factor (e.g., a t2.medium instance has a normalization factor of two so a reservation for four t2.medium instances would have an instance size footprint of eight units). Knowing the instance size footprint associated with a reservation allows you to compare that usage with other usage incurred in the same instance family.

Using AWS Cost Explorer, you can dive deeper by adjusting your usage to display as normalized units (which takes the reservation’s instance size footprint into account) in order to gain a more complete understanding of how your reservation portfolio is being applied to your usage. Additionally, you can use AWS Cost Explorer's RI Coverage Report to filter by a particular instance family to view all associated costs and usage. You can save your progress as a custom report at any time and refer back to it later.

Please note that you can also access normalized units information via the AWS Cost Explorer API.

To learn more about using AWS Cost Explorer to manage your reservations, please refer to the Reserved Instance Reporting webpage or the Analyzing your costs with Cost Explorer user guide. You can access AWS Cost Explorer directly here.