AWS Cost Explorer Service
Cost Management APIs


Creates recommendations that helps you save cost by identifying idle and underutilized Amazon EC2 instances.

Recommendations are generated to either downsize or terminate instances, along with providing savings detail and metrics. For details on calculation and function, see Optimizing Your Cost with Rightsizing Recommendations.

Request Syntax

{ "Filter": { "And": [ "Expression" ], "Dimensions": { "Key": "string", "Values": [ "string" ] }, "Not": "Expression", "Or": [ "Expression" ], "Tags": { "Key": "string", "Values": [ "string" ] } }, "NextPageToken": "string", "PageSize": number, "Service": "string" }

Request Parameters

For information about the parameters that are common to all actions, see Common Parameters.

The request accepts the following data in JSON format.


Use Expression to filter by cost or by usage. There are two patterns:

  • Simple dimension values - You can set the dimension name and values for the filters that you plan to use. For example, you can filter for REGION==us-east-1 OR REGION==us-west-1. The Expression for that looks like this:

    { "Dimensions": { "Key": "REGION", "Values": [ "us-east-1", “us-west-1” ] } }

    The list of dimension values are OR'd together to retrieve cost or usage data. You can create Expression and DimensionValues objects using either with* methods or set* methods in multiple lines.

  • Compound dimension values with logical operations - You can use multiple Expression types and the logical operators AND/OR/NOT to create a list of one or more Expression objects. This allows you to filter on more advanced options. For example, you can filter on ((REGION == us-east-1 OR REGION == us-west-1) OR (TAG.Type == Type1)) AND (USAGE_TYPE != DataTransfer). The Expression for that looks like this:

    { "And": [ {"Or": [ {"Dimensions": { "Key": "REGION", "Values": [ "us-east-1", "us-west-1" ] }}, {"Tags": { "Key": "TagName", "Values": ["Value1"] } } ]}, {"Not": {"Dimensions": { "Key": "USAGE_TYPE", "Values": ["DataTransfer"] }}} ] }


    Because each Expression can have only one operator, the service returns an error if more than one is specified. The following example shows an Expression object that creates an error.

    { "And": [ ... ], "DimensionValues": { "Dimension": "USAGE_TYPE", "Values": [ "DataTransfer" ] } }


For GetRightsizingRecommendation action, a combination of OR and NOT is not supported. OR is not supported between different dimensions, or dimensions and tags. NOT operators aren't supported. Dimensions are also limited to LINKED_ACCOUNT, REGION, or RIGHTSIZING_TYPE.

Type: Expression object

Required: No


The pagination token that indicates the next set of results that you want to retrieve.

Type: String

Required: No


The number of recommendations that you want returned in a single response object.

Type: Integer

Valid Range: Minimum value of 0.

Required: No


The specific service that you want recommendations for. The only valid value for GetRightsizingRecommendation is "AmazonEC2".

Type: String

Required: Yes

Response Syntax

{ "Metadata": { "GenerationTimestamp": "string", "LookbackPeriodInDays": "string", "RecommendationId": "string" }, "NextPageToken": "string", "RightsizingRecommendations": [ { "AccountId": "string", "CurrentInstance": { "CurrencyCode": "string", "MonthlyCost": "string", "OnDemandHoursInLookbackPeriod": "string", "ReservationCoveredHoursInLookbackPeriod": "string", "ResourceDetails": { "EC2ResourceDetails": { "HourlyOnDemandRate": "string", "InstanceType": "string", "Memory": "string", "NetworkPerformance": "string", "Platform": "string", "Region": "string", "Sku": "string", "Storage": "string", "Vcpu": "string" } }, "ResourceId": "string", "ResourceUtilization": { "EC2ResourceUtilization": { "MaxCpuUtilizationPercentage": "string", "MaxMemoryUtilizationPercentage": "string", "MaxStorageUtilizationPercentage": "string" } }, "SavingsPlansCoveredHoursInLookbackPeriod": "string", "Tags": [ { "Key": "string", "Values": [ "string" ] } ], "TotalRunningHoursInLookbackPeriod": "string" }, "ModifyRecommendationDetail": { "TargetInstances": [ { "CurrencyCode": "string", "DefaultTargetInstance": boolean, "EstimatedMonthlyCost": "string", "EstimatedMonthlySavings": "string", "ExpectedResourceUtilization": { "EC2ResourceUtilization": { "MaxCpuUtilizationPercentage": "string", "MaxMemoryUtilizationPercentage": "string", "MaxStorageUtilizationPercentage": "string" } }, "ResourceDetails": { "EC2ResourceDetails": { "HourlyOnDemandRate": "string", "InstanceType": "string", "Memory": "string", "NetworkPerformance": "string", "Platform": "string", "Region": "string", "Sku": "string", "Storage": "string", "Vcpu": "string" } } } ] }, "RightsizingType": "string", "TerminateRecommendationDetail": { "CurrencyCode": "string", "EstimatedMonthlySavings": "string" } } ], "Summary": { "EstimatedTotalMonthlySavingsAmount": "string", "SavingsCurrencyCode": "string", "SavingsPercentage": "string", "TotalRecommendationCount": "string" } }

Response Elements

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.


Information regarding this specific recommendation set.

Type: RightsizingRecommendationMetadata object


The token to retrieve the next set of results.

Type: String


Recommendations to rightsize resources.

Type: Array of RightsizingRecommendation objects


Summary of this recommendation set.

Type: RightsizingRecommendationSummary object


For information about the errors that are common to all actions, see Common Errors.


The pagination token is invalid. Try again without a pagination token.

HTTP Status Code: 400


You made too many calls in a short period of time. Try again later.

HTTP Status Code: 400

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: