CloudZero has developed a standard data model to ingest cost data from any source, called the Common Bill Format (CBF).

The CBF is modeled after the AWS CUR format, but is simpler and more generic. This allows the CBF to be used by many different cloud providers.

If you use an AnyCost Bucket Adaptor, write the CBF to a gzipped CSV file and upload a manifest.json with it. See Configuring AnyCost Bucket File Drops.

If you use an AnyCost Stream Adaptor, send the CBF to the CloudZero AnyCost API in a JSON request body. See Sending AnyCost Stream Data to CloudZero.

Data file columns

datetime values should be ISO-formatted strings in the UTC timezone. Excel often auto-converts ISO-formatted dates to a human-readable format. Ensure dates are saved correctly in your CSV file.

Note: resource/id is required only when a resource/tag:<key> value is included for the charge.

Line Item columns

lineitem/id

Uniquely identifies this specific line item in this specific bill.

lineitem/type

Broad category of this line item: Usage, Tax, Discount, and so on. Values have special meaning (see below). If not provided, assumed to be Usage.

The lineitem/type column defines how each line items should be interpreted.

The following values are supported:

lineitem/description

An optional description specifying additional information about this line item.

lineitem/cloud_provider

A string value identifying the underlying cloud provider for each line item, for example, Anthropic, OpenAI, AWS, Azure, which is particularly useful for aggregator services that consolidate billing from multiple cloud providers into a single CBF file.

Time columns

time/usage_start

The hour during which the charged usage applies. This value should be aligned to the start of the hour and will be treated as such. Note, the current version of the Common Billing Format does not use usage_end date.

time/usage_end

The end of a timespan to which the charged usage applies. Note that although this may be specified, all changes are treated as occurring in a single hour at usage_start. Future updates to the ingest process may take advantage of the usage_end value.

Resource columns

resource/id

Uniquely identifies the object for which this charge applies. This column is required if any resource/tag:<key> columns are included.

• The resource/id is the unique identification of the resource for which the charge applies.
• The following special characters : / have special meaning and should be used carefully
  • A resource/id containing one of the above characters will be split and the second element will be taken as the resource/id (for example, a resource/id of abc will become b)
• When resource/id is specified, you may also provide resource/tag:<key> columns to categorize the resource by <key>, which may be a purpose, owner, environment, or other criteria.
  • When including resource/tag:<key> data with a charge, the resource/id column is required.
  • Only oneresource/tag:<key> column <value> will be associated with each unique resource/id value. For more information, see the Resource Tags section below.

resource/service

The category to which this resource belongs. Generally represents different kinds of services provided by the Cloud Provider for which the customer is charged.

resource/account

The account or project to which this resource belongs (if applicable).

resource/region

The region to which this resource belongs (if applicable).

resource/usage_family

Commonly a subdivision of resource/service

resource/tag:<key>

Custom attributes associated with the resource. The <key> is case sensitive, and can consist of letters, numbers, and the following special characters _ . : / = + - @.. Using this column also requires resource/id to be populated.

• resource/tag:<key> columns allow you to categorize resources by purpose, owner, environment, or any other criteria.
• The <key> is case sensitive, and can consist of letters, numbers, and the following special characters _ . : / = + - @..
  • No spaces, tabs or returns are allowed.
  • For example, resource/tag:team or resource/tag:Product-Type are valid tag keys, while resource/tag:Team Name and resource/tag:Product&Dev are not.
• resource/tag:<key> will appear as Tag dimensions in the CloudZero platform, and can be used to filter or aggregate the cost of the tagged resources.
• You may include as many unique resource/tag:<key> columns as you need.
• Only one <value> will be associated with a resource/tag:<key> column for each unique resource/id.
  • If multiple values are supplied for the same ID, the value with the latest time/usage_start will be used.
  • If all instances for a given key have identical time/usage_start dates, then one is arbitrarily selected.
• The latest <value> of a given resource/tag:<key> for each resource/id will be retroactively applied to all data in the CloudZero system with the same resource/id.

resource/id and resource/tag usage example

B Large, Inc. is using the CloudZero platform to monitor their cloud costs, and needs to easily identify their resources by the teams that own them. To assist with this, B Large creates a Resource Tag called resource/tag:team, and populates it with the names of the various teams that own the AWS resources in question.

Team Alpha owns an AWS Lambda function with ther esource/id of making-great-calculations. Since these resources have been tagged as owned by Team Alpha using the resource/tag:team key with the value of Alpha, whenever anyone logs into CloudZero, they can easily use the team``Tag Dimension to view what Alpha's Lambda is costing B Large, and monitor trends over time.

Recently, B Large promoted more personalized team names, and Team Alpha voted to name themselves Team Batman. With this change, the resource/tag:team value in AWS is updated to reflect their new name, and CloudZero receives a new data drop that associates a new resource/tag:team value of Batman with the AWS Lambda function resource/idof making-great-calculations.

The CloudZero platform receives this updated tag information, and because only one value per resource/tag:team can be associated with a single resource/id of making-great-calculations, the platform retroactively applies this new tag to all historical data in the system for the resource/id of making-great-calculations.

Now when anyone at B Large logs into CloudZero, they can still see what Team Batman owns, and because the tag change was retroactively applied to all historical data, the monitoring of trends over time for the making-great-calculations Lambda sees no interruption, and reports continue to accurately reflect totals and trends, including those that were ingested prior to Team Batman's name change.

Action columns

action/operation

The thing that was done to the resource for which you are being charged.

action/usage_type

Commonly a subdivision of action/operation.

action/region

Deprecated; use resource/region. The region in which the operation was performed. May not match the resource/region for cross-region operations.

action/account

Deprecated; use resource/account. The account in which the operation was performed. May not match the resource/account for cross-region operations.

Usage columns

usage/amount

A numeric value describing an amount consumed or used, for example, GB stored or transferred, seconds executed, credits consumed.

usage/units

A description of the units used for usage/amount.

Cost columns

There are five cost category columns cost, discounted_cost, amortized_cost, discounted_amortized_cost, and on_demand_cost. Only cost is required, but the others may be used to help smooth out charges not directly associated with the use of cloud services.

cost/cost

The cost associated with this line item. May be negative for line items which represent discounts or credits. Sometimes referred to as unblended cost, billed cost, or invoiced cost.

cost/discounted_cost

The net cost associated with this line item after any discounts, credits, or private pricing are applied. Sometimes referred to as net cost or net unblended cost.

cost/amortized_cost

The effective cost associated with this line item after any committed use purchases, for example, AWS RIs or Savings Plans, GCP CUDs, and so on, are amortized over all the Usage line items to which they apply.

cost/discounted_amortized_cost

The net effective cost associated with this line item after any discounts, credits, or private pricing are applied. It also includes any committed use purchases, for example, AWS RIs or Savings Plans, GCP CUDs, and so on, amortized over all the Usage line items to which they apply. Sometimes referred to as net amortized cost, net effective cost, or fully-loaded cost.

cost/on_demand_cost

The cost of this line item if no mechanism for reducing costs had been applied. In other words, it is the cost as if there were no discounts, applicable committed use purchases, private pricing, and so on. This is often useful for determining one's effective savings rate.

Precedence for cost columns

To ensure all cost columns are fully populated and may be used in the platform, blank values will fall back and use a different cost column. For example, if discounted_amortized_cost is left blank, discounted_cost will be used instead. The assumption is that no line items required amortization, that is, there are no committed use purchases, and thus the discounted cost could be used instead. Only blank or empty values trigger this behavior; if the value is set to 0, it will be used as is. The complete set of fallback logic is:

• discounted_amortized_cost → amortized_cost → discounted_cost → cost
• amortized_cost → cost
• discounted_cost → cost
• on_demand_cost → cost

The total value across all line items for each of cost, discounted_cost, amortized_cost, and discounted_amortized_cost should be the same. Each represents a redistribution of charges (discounts or purchases or both), not the inclusion or exclusion of charges. This equivalence is not enforced by the billing ingest system, but may be in the future.

How cost types are defined

CloudZero cost types are defined in terms of the lineitem/type and different cost category columns.

• Real Cost: Only Usage line item types are included. The discounted_amortized_cost column is used, if present, with fallback logic to the other cost values if it is not.
• Discounted Amortized Cost - All line item types are included. The discounted_amortized_cost column is used, if present, with fallback logic to the other cost categories if it is not.
• Amortized Cost - All line item types are included. The amortized_cost column is used, if present, with fallback to cost if not.
• Discounted Cost - All line item types are included. The discounted_cost column is used, if present, with fallback to cost if not.
• On-Demand Cost - All line item types are included. The on_demand_cost column is used, if present, with fallback to cost if not.
• Billed Cost - All line item types are included. The cost column is used.

Bill column

bill/invoice_id

Uniquely identifies a particular bill. A single billing data ID for a single month may include multiple invoices. Ideally this field will not be populated until an Invoice is closed.

Kubernetes columns

k8s/cluster

The Kubernetes cluster associated with the resource.

k8s/namespace

The Kubernetes namespace associated with the resource.

k8s/deployment

The Kubernetes deployment associated with the resource.

k8s/labels

The Kubernetes labels associated with the resource.

CBF examples

Compute purchase from Simple Cloud example

In this example we purchased some Compute from Simple Cloud. We also made an up-front committed use purchase, which lowered the normal hourly rate by 50%. Simple Cloud is running a promotion, so we received the SpecialCompute discount for using a certain Compute instance type. We also received the MVP Discount.

This first version of the bill just includes the actual charges. The cost for our Compute instances is at the reduced rate because of the committed use purchase; for example, instance-0000 would have otherwise cost $24 during that hour. The sum of the values in the cost/cost column should equal exactly what we see on the bill for March: $105.30

Discounted cost example

It would be helpful if the discount we received for using the promoted Compute instances were actually represented in the cost of those instances. In this example we will include the cost/discounted_cost.

The SpecialCompute discount was distributed evenly over the individual instances. We also zeroed out the cost for the SpecialCompute line item because that discount has already been accounted for. We chose not to distribute the MVPDiscount since it was unrelated to the Compute instances. We copied over the values for the CommitedUse purchase and MVPDiscount, but we could have also left them blank and the cost/cost value would have been used by default.

Amortized cost example

To help our engineers better understand the real cost of those Compute instances, we also want to include what we paid for the CommitedUse purchase.

The cost of the CommitedUse purchase was evenly distributed over all the Compute instances to which it applied, which in this case was all of them. We left the cost/amortized_cost for the Discounts blank. We could have also copied over the values from the discounted_cost (0 and -20). The important thing is that the the sum of the values in the cost/amortized_cost column, including the default values for the blank cells, is still: $105.30

Kubernetes-related columns example

In this example, we add Kubernetes-related columns to the existing CBF data to provide more context on resource usage within a Kubernetes environment.

Kubernetes-related information such as cluster, namespace, deployment, and labels is included. This allows tracking usage and costs within specific Kubernetes contexts.