Rightsizing End Points


The Rightsizing API provides rightsizing recommendations for resources from supported services. For each of these resources, the API returns multiple optimization recommendations as well as descriptive information such as the current instance size, cost, idle percentage, and recommended action(s). Read more about Rightsizing


These endpoints are read-only and are used for obtaining a list of rightsizing recommendations for your cloud resources, for these supported services:

Amazon Web Services

  • EC2EC2 - Elastic Cloud Compute: /rightsizing/aws/recommendations/ec2
  • EBS: /rightsizing/aws/recommendations/ebs
  • RDS: /rightsizing/aws/recommendations/rds
  • S3: /rightsizing/aws/recommendations/s3

Microsoft Azure

  • Compute (VMs) : /rightsizing/azure/recommendations/compute
  • Managed Disk : /rightsizing/azure/recommendations/disk
  • SQL Database : /rightsizing/azure/recommendations/sql

The endpoints return a meta attribute within the JSON payload that looks like the following. In the example below 4783 represents the count of resources, $337,029.28 their total cost, $930.84 the potential savings by addressing idle resources and $106,857.60 potential savings through rightsizing. This leaves $229,240.04 for resources considered already optimized. These numbers are for the ten day reporting period.

"meta": {
    "totalCount": 4783,
    "aggregates": [
        "basis": "On-Demand",
        "cost": 337029.28,
        "idleSavings": 930.84,
        "rightsizeSavings": 106857.60,
        "optimizedSavings": 229240.84

Request Parameters



basis (required)

The cost basis used.

Values are on-demand or effective

Default = on-demand

Note: the effective cost basis is available for EC2 and RDS services

duration (required)

The look back period in days, used for calculating the recommendations.

Valid values are : ten-day and thirty-day
Default = ten-day

Note: only thirty-day is available for S3


Filter the resources based on an attribute of your choice.
Example: filters=recommendations.action==Rightsize. To base on attribute within recommendation itself prefix with 'recommendations.'. Multiple filters can be chained together with commas. Example: filters=recommendations.savings>20,recommendations.risk==0
Read More for more details on filtering.

limit (required)

Used together with offset to provide pagination. Example: limit=10. default = 50


Set a maximum number of recommendations to be delivered with each resource.
Example: maxRecsPerResource=10
default = 1


Used together with limit to provide pagination.
Example: offset=0
default = 0


Product Name, Example ec2, ebs, s3


Sort the resources based on an attribute of your choice. [Read More]] https://developers.cloudability.com/docs/getting-started#section-sorting) about sorting.

Example: sort=-name
(sort by name descending)

Default: sort=-recommendations.savings ( sort resources with highest savings potential descending)


Source system for utilization data
Examples: datadog, cloudwatch


Filter to a list of vendor accounts. Separate accounts using commas.
Example: vendorAccountIds=999988887777,111122223333


The number of the View If blank, the view will be your default view.

Note: The default rightsizing report (i.e a call to /rightsizing/aws/recommendations/ec2 without any query arguments) will give you 50 EC2 instances ordered by highest savings descending. There will be 5 recommendations with each resource. There will be no filtering applied outside of the view you have applied.

The Resource Object

Current Resource Summary

The result object contains a list of all matching resources. This is the summary data included with each:

service (string) - Name of Recommendation Service (ec2-recs, eb2,rec, etc)
name (string) - Name of the resource. Originates from the Name tag
resourceIdentifier (string) - The unique identifier provided by the vendor for the resource
vendorAccountId (string) - The unique identifier for the account the resource exists within
tagMappings (array) - list of tag key and value pairs of tag mappings
      tag (string) - native/provider tag name
      tagName (string) - name/key for tag mapping
      vendorTagValue (string) - value for this tag
availabilityZone (string) - The availability zone the resource resides in
provider (string) - The source provider, for example, NATIVE
region (string) - The region the resource resides in
os (string) - The operating system of the resource
nodeType (string) - For EC2 this is the instance type of the resource
unitPrice (number) - The per unit rate
effectiveHourly (number) - The hourly rate charged for the resource based on effective rates. DEPRECATED. Instead will show as unitPrice when costBasis=effective.
totalSpend (number) - The entire cost for the resource over the last 10 or 30 days
idle (number) - represents the percentage of time the resource has been idle
localCapacity (number) - local EC2 instance storage in GB. Types without associated storage will have a value of -1
localDrives (number) - number of local drives attached to the instance. Types without associated storage will have a value of -1
cpuCapacity (number) - count of CPU cores for current instance
memoryCapacity (number) - memory capacity for current instance in GB
networkCapacity (number) - network capacity for current instance in GB
lastSeen (datetime) - date resource was last seen
tenancy (string) - deprecated
hoursRunning (number) - hours running within period
cpuMax (number) - max CPU percentage during period
memoryMax (number) - max Memory percentage during period
defaultSameFamily (boolean) - use same instance family
defaultCurrentGen (boolean) - use current generations
defaultMemoryFit (boolean) - use same memory specification

Recommendation List

For each resource listed there will be a recommendations attribute which is an associated list of recommendation objects. These are the attributes of each recommendation:
recommendations (array) - A list of recommendations for the resource. Described below
      action (string) - what action to take: rightsize, terminate, autoscale
      preferenceOrder (number) - deprecated
      defaultsOrder (number) - deprecated
      nodeType (string) - the target instance type
      localCapacity (number) - local EC2 instance storage in GB for target resource
      localDrives (number) - number of local drives attached to target instance
      cpuCapacity (number) - count of CPU cores for target instance
      memoryCapacity (number) - memory capacity for target instance in GB
      networkCapacity (number) - network capacity of target instance
      previousGenTarget (boolean) - Is target instance a previous generation type?
      currentGen (boolean) - Is target instance a current generation type?
      sameMemory (boolean) - use same memory size as source instance
      sameFamily (boolean) - Is the target instance type within the same family
      unitPrice (number) - The per unit rate
      cpuRatio (number) - ratio of CPU cores (target/original)
      memoryRatio (number) - ratio of memory capacity (target/original)
      diskXPutCapacity (number) - ratio of memory capacity (target/original)
      networkRatio (number) - ratio of network throughput capacity (target/original)
      cpuRisk (number) - risk related to CPU - value between 0 and 5 TBC. 0 being zero risk
      memoryRisk (number) - risk related to memory - value between 0 and 5 TBC
      diskRisk (number) - local disk throughput risk - value between 0 and 5 TBC
      networkRisk (number) - risk related to network throughput - value between 0 and 5 TBC
      risk (number) - value of 0,1,2,3,4 or 5. 0 being no risk. 5 being highest risk
      savingsPct (number) - Savings as a percentage by moving to target type
      savings (number) - Savings over the last 10 or 30 days if you had used the target type
      inDefaults - deprecated
      memoryFit deprecated
      persistentStorageAdded TBC - we added EBS costs for say c3 to c4

Example Object

"result": [
      "service": "ec2-recs",
      "name": "My EC2 Instance",
      "resourceIdentifier": "i-5b234a4fae415b77f",
      "vendorAccountId": "458273444843",
      "tagsMappings: [
          "tagName": "tag_user_Environment",
          "vendorTagValue": "production"
          "tagName": "tag_user_Name",
          "vendorTagValue": "My EC2 Instance"
      "availabilityZone": "ap-southeast-2b",
      "provider": "NATIVE"
      "region": "ap-southeast-2",
      "os": "Linux",
      "nodeType": "i3.8xlarge",
      "unitPrice": 1.81,
      "totalSpend": 434.11,
      "idle": 0,
      "localCapacity": 7600,
      "localDrives": 4,
      "cpuCapacity": 32,
      "memoryCapacity": 244,
      "networkCapacity": 10000,
      "lastSeen": "2019-10-31T23:00:00Z",
      "tenancy" : "default",
      "hoursRunning": 240,
      "cpuMax": 6,
      "memoryMax": 6,
      "recommendations": [
          "action": "Rightsize",
          "preferenceOrder": 1,
          "defaultsOrder": 1,
          "nodeType": "x1e.xlarge",
          "localCapacity": 120,
          "localDrives": 1,
          "cpuCapacity": 4,
          "memoryCapacity": 122,
          "previousGenTarget": false,
          "currentGen": true,
          "sameMemory": false,
          "sameFamily": false,
          "unitPrice": 0.83,
          "cpuRatio": 0.13,
          "memoryRatio": 0.5,
          "diskXPutCapacity": 100,
          "networkRatio": 1,
          "cpuRisk": 0,
          "memoryRisk": 0,
          "diskRisk": 0,
          "networkRisk": 0,
          "risk": 0,
          "savingsPct": 54,
          "savings": 233.95,
          "inDefaults": true,
          "memoryFit": false,
          "persistentStorageAdded": false
      "defaultSameFamily": false,
      "defaultCurrentGen": true,
      "defaultMemoryFit": false

Some Important Attributes

There are a few attributes worth a special mention

  • risk: This is the graded risk for an individual recommendation. risk can take a value of 0,1,2,3,4 or 5. 0 implies that we expect the recommendation to have sufficient headroom for your resource without any clipping. 1 through 5 indicate increasing risk that performance could be affected. Note that there is a total risk score as well as individual ones for CPU, Network, Memory and Disk.
  • rank: rank is based on a grouping system of risk and savings. The highest ranking recommendation will come from the cohort with lowest risk. From that cohort it will pick the one with the highest savings. The next in line ranking wise will come from the cohort with second lowest risk, and again highest savings. Rank is established as such by cycling through these risk cohorts until all recommendations as ranked. See special notes at bottom of page for extra ranking options.


# full list of 10-day dataset EC2 recommendations:

curl "https://api.cloudability.com/v3/rightsizing/aws/recommendations/ec2?limit=5&maxRecsPerResource=1&offset=0&duration=ten-day" -u api-token:
## full list of 30-day dataset EBS recommendations:

curl "https://api.cloudability.com/v3/rightsizing/aws/recommendations/ebs?limit=5&maxRecsPerResource=1&offset=0&duration=thirty-day" -u apikey:
##Give me the full list of 10-day dataset Azure Compute recommendations:

curl "https://api.cloudability.com/v3/rightsizing/azure/recommendations/compute?basis=cost&filters=recommendations.sameFamily%3D%3D1&limit=25&maxRecsPerResource=10&offset=0&product=compute&sort=-recommendations.savings&sortField=recommendations.savings&sortOrder=desc&duration=ten-day&vendorAccountIds&viewId=0" -u apikey:

(using Cloudability's default ranking); Order resources by biggest savings descending. This results set will match what you see in the summary page of our rightsizing console.

## Give me just the default recommendation per resource

curl "https://api.cloudability.com/v3/rightsizing/aws/recommendations/ec2?rank=default&maxRecsPerResource=1&sort=-recommendations.savings" -u apikey:
# Give me all the recommendations for a particular resource/instance id

curl "https://api.cloudability.com/v3/rightsizing/aws/recommendations/ec2?filters=resourceIdentifier==i-ae3f332111" -u apikey:
## Give me recommendations just for specific accounts

curl "https://api.cloudability.com/v3/rightsizing/aws/recommendations/ec2?accountIds=999988887777,111122223333" -u apikey:
## Filter my recommendations based on tags

curl "https://api.cloudability.com/v3/rightsizing/aws/recommendations/ec2?filters=tag_user_<tag_key>==<tag_value>" -u apikey:

Special Notes

To add another layer to this ranking system you can add rank=default as a query parameter. This will prioritize 2 extra attributes, memoryFit and currentGen before going through the risk/savings routine. currentGen for example would make sure that m4s (a current generation) would get recommended ahead of m1s (previous generation). Recommendations can be memoryFit through two different means 1) Cloudability has received the memory data and identified a fit or 2) Cloudability hasn't received the memory data so memoryFit will only include instance types which have matching memory or higher.