Best practices for understanding your AWS billing and usage reports in DynamoDB

This document explains the UsageType billing codes for charges related to DynamoDB.

AWS provides cost and usage reports (CUR) that contain data for the services used. You can use AWS Cost and Usage Report to publish billing reports to Amazon S3 in a CSV format. When setting up the CUR you can choose to break time periods down by hour, day, or month, and you can choose if you want to break out usage by resource ID or not. For more details on generating CUR, please see Creating Cost and Usage Reports

Within the CSV export, you will find relevant attributes listed for each line. The following are examples of attributes that may be included:

For more information about the CUR data dictionary, see Cost and Usage Report (CUR) 2.0. Note that the exact names vary depending on context.

A UsageType is a string with a value such as ReadCapacityUnit-Hrs, USW2-ReadRequestUnits, EU-WriteCapacityUnit-Hrs, or USE1-TimedPITRStorage-ByteHrs. Each usage type begins with an optional Region prefix. If absent, that indicates the us-east-1 Region. If present, the below table maps the short billing Region code to the conventional Region code and name.

For example, the usage named USW2-ReadRequestUnits indicates read request units consumed in us-west-2.

In the following sections, we use REG-UsageType pattern when going through the charges for DynamoDB, where REG specifies the region where usage occurred and usageType is the code for the type of charge. For example if you see a line item for USW1- ReadCapacityUnit-Hrs in your CSV file, that means the usage was incurred in US-West-1 for provisioned read capacity. In that case the listing would say REG-ReadCapacityUnit-Hrs.

Throughput Capacity

Provisioned Capacity Reads and Writes

When you create a DynamoDB table in provisioned capacity mode, you specify the read and write capacity that you expect your application to require. The usage type depends on your table class (Standard or Standard-Infrequent Access). You provision read and writes based on consumption rate per second, but the charges are priced per hour based on provisioned capacity.

Reserved Capacity Reads and Writes

With reserved capacity, you pay a one-time upfront fee and commit to a minimum provisioned usage level over a period of time. Reserved capacity is billed at a discounted hourly rate. Any capacity that you provision in excess of your reserved capacity is billed at standard provisioned capacity rates. Reserved capacity is available for single-region, provisioned read and write capacity units (RCU and WCU) on DynamoDB tables that use the standard table class. Both 1-year and 3-year reserved capacity are billed using the same SKUs.

On-Demand Capacity Reads and Writes

When you create a DynamoDB table in on-demand capacity mode, you pay only for the reads and writes your application performs. The prices for read and write requests depend on your table class.

Global Tables Reads and Writes

DynamoDB charges for global tables usage based on the resources used on each replica table. For provisioned global tables, write requests for global tables are measured in replicated WCUs (rWCU) instead of standard WCUs and writes to global secondary indexes in global tables are measured in WCUs. For on-demand global tables, write requests are measured in replicated WRUs (rWRU) instead of standard WRUs. The number of rWCUs or rWRUs consumed for replication depends on the version of global tables you are using. The pricing depends on your table class.

Writes to global secondary indexes (GSIs) are billed using standard write units (WCUs and WRUs). Read requests and data storage are billed identically to single-region tables.

If you add a table replica to create or extend a global table in new Regions, DynamoDB charges for a table restore in the added Regions per gigabyte of data restored. Restored Data is charged as REG-RestoreDataSize-Bytes. Please refer to Backup and restore for DynamoDB for details. Cross-Region replication and adding replicas to tables that contain data also incur charges for data transfer out.

When you select on-demand capacity mode for your DynamoDB global tables, you pay only for the resources your application uses on each replica table.

Streams

DynamoDB has two streaming technologies, DynamoDB Streams and Kinesis. Each have separate pricing.

DynamoDB Streams charges for reading data in read request units. Each GetRecords API call is billed as a streams read request. You are not charged for GetRecords API calls invoked by AWS Lambda as part of DynamoDB triggers or by DynamoDB global tables as part of replication.

Amazon Kinesis Data Streams charges in change data capture units. DynamoDB charges one change data capture unit for each write (up to 1 KB). For items larger than 1 KB, additional change data capture units are required. You pay only for the writes your application performs without having to manage throughput capacity on the table.

Storage

DynamoDB measures the size of your billable data by adding the raw byte size of your data plus a per-item storage overhead that depends on the features you have enabled.

Storage is calculated hourly but priced monthly as calculated from an average of the hourly charges.

Although the storage UsageType uses ByteHrs as a suffix, storage usage in the CUR is measured in GB and priced by GB-month.

Backup and Restore

DynamoDB offers two types of backups: Point In Time Recovery (PITR) backups and on- demand backups. Users can also restore from those backups into DynamoDB tables. The charges below refers to both backups and restores.

Backup storage charges are incurred on the first of the month with adjustments made throughout the month as backups are added or removed. See the Understanding Amazon DynamoDB On-demand Backups and Billing blog for more information

AWS Backup

AWS Backup is a fully managed backup service that makes it easy to centralize and automate the backup of data across AWS services in the cloud as well as on premises. AWS Backup is charged for storage (warm or cold storage), restoration activities, and cross-Region data transfer. The following UsageType charges appear under the “AWSBackup” ProductCode rather than “AmazonDynamoDB”.

Export and Import

You can export data from DynamoDB to Amazon S3 or import data from Amazon S3 to a new DynamoDB table.

Although the UsageType uses Bytes as a suffix, export and import usage in the CUR is measured and priced in GB.

Data Transfer

Data transfer activity may appear associated with the DynamoDB service. DynamoDB does not charge for inbound data transfer, and it does not charge for data transferred between DynamoDB and other AWS services within the same AWS Region (in other words, $0.00 per GB). Data transferred across AWS Regions (such as between DynamoDB in the US East [N. Virginia] Region and Amazon EC2 in the EU [Ireland] Region) is charged on both sides of the transfer.

CloudWatch Contributor Insights

CloudWatch Contributor Insights for DynamoDB is a diagnostic tool for identifying the most frequently accessed and throttled keys in your DynamoDB table. The following UsageType charges appear under the “AmazonCloudWatch” ProductCode rather than “AmazonDynamoDB”.

DynamoDB Accelerator (DAX)

DynamoDB Accelerator (DAX) is billed by the hour based on the instance type selected for the service. The charges below refers to the DynamoDB Accelerator instances provisioned. The following UsageType charges appear under the “AmazonDAX” ProductCode rather than “AmazonDynamoDB”.

The instance type will be one of the values from the following list. For details about node types, see Nodes.