Cost Explorer vs Cost and Usage Report (CUR): How to Use Them Correctly

07-02-2025 / Cost Optimization Strategies / 7 mins.

A significant problem led Amazon to introduce Cost Explorer and Cost and Usage Reports. Many Amazon Web Services (AWS) users were overspending on services they couldn't clearly identify.

Before these two cloud financial management tools, the AWS public cloud was like a buffet without price tags. Engineers could use as many cloud resources as they wanted (and then some), only to face surprise bills at the end of the month or billing cycle.

However, Cost Explorer and Cost and Usage Reports (CUR) can seem like two sides of the same coin.

So, what are the differences between Cost Explorer and CUR?

a) Quick Summary

	AWS Cost and Usage Report	AWS Cost Explorer
Description	A comprehensive, spreadsheet-like report containing billing data for an AWS Payer account.	Highly visual cost charts and tables that display a relatively high-level view of your cost and usage data for a specific AWS Payer account.
Unique Functionality	Provides historical cost and usage data details and delivers them to an Amazon S3 bucket for further analysis and long-term retention.	Not only provides historical records, but also creates forecasts and savings recommendations.
Data Fields	Multiple data lines. Also supports Cost Categories and Cost Allocation Tags.	Up to 18 filters and groupings.
Format	CSV and Parquet	CSV
Cost Data Duration	Hourly, daily, and monthly.	Hourly (up to 14 days), daily, and monthly.
Pricing	Free, but standard Amazon S3 charges apply.	Free, although querying cost and usage data through the Cost Explorer API costs $0.01 per paginated request.

b) What Does AWS Cost Explorer Do?

Once you enable AWS Cost Explorer on the Payer account, the tool collects and reports cost and usage data from all member accounts linked to it.

After a period of use, Cost Explorer can generate cost and usage reports for up to the past 12 months, plus the current month. It analyzes this historical data to create a three-month forecast of your future costs and usage patterns.

In the main chart, you can visualize the five AWS services driving the most costs. The table view, on the other hand, lets you examine the cost and usage data for all your services.

You can also use up to 18 cost filters to identify where your money is being spent. These filters include views by instance type, cost category, resource, region or availability zone, service, and linked account.

Additionally, you can view cost data by the hour (for 14 days) and with resource-level granularity (unlimited duration). If you need more detailed reports, you can obtain them on a daily and monthly basis.

Additional features: AWS Cost Explorer allows you to generate two types each of Savings Plans and Reservations reports.

1. Savings Plans Utilization Report: Visualize your cumulative Savings Plan usage and set a custom utilization target. This report makes it easy to understand how well you are leveraging the resources you have purchased.
2. Savings Plans Coverage Report: Represents the overall coverage of your Savings Plans and lets you set a custom target. The report is designed to identify savings opportunities.
3. Reservations Utilization Report: Shows how much of your reserved resources you have used, helping you understand how effectively you are leveraging them. It also allows you to set a custom target.
4. Reservations Coverage Report: Lets you view the total coverage of your reservations and define a custom target, helping you spot savings opportunities.

In addition, AWS Cost Explorer can generate up to 50 custom cost and usage reports simultaneously, in CSV format, to share with multiple stakeholders.

Customization: You can use the AWS Cost Explorer API to build interactive, custom cost management applications without needing to set up additional infrastructure. However, AWS charges $0.01 per paginated request, counting each page as an individual request.

Cost Explorer also helps identify underutilized EC2 instances that you could downsize within the same instance family. It also factors in your Reservations and Savings Plans to analyze the potential impact on your bill.

It generates personalized recommendations across all commercial regions (except China) for instance families A, T, M, C, R, X, Z, I, D, and H. However, Cost Explorer does not apply changes automatically, unlike tools such as ProsperOps.

c) What Is the Cost and Usage Report (CUR) Used For?

It provides a detailed view of resource usage and associated costs in raw format.

CUR reports offer the most granular billing data of any cost management tool in AWS, including Cost Explorer. This includes hourly, daily, monthly, per-product, per-service, per-resource, and custom tag data.

Key Details:

• A CUR allows you to create and save cost and usage data in an Amazon S3 bucket for later analysis.
• You can download the data in CSV format (compressed as GZIP) or Parquet to work with tools like Amazon QuickSight.
• To ensure the CUR in S3 is constantly updated, select the "Overwrite existing report" option.
• Enables integration with other analytics tools such as Amazon Athena, Amazon QuickSight, and Amazon Redshift.

AWS updates your CUR in S3 at least once a day, up to three times daily.

d) Difference Between Cost Explorer and CUR

• Cost Explorer: Provides a high-level, simplified view of costs and resource consumption, with visual charts, forecasts, and savings recommendations. It is ideal for quick analysis and planning based on historical data.
• CUR: Offers a detailed breakdown of costs and usage down to the resource level. It generates comprehensive reports that can be stored in S3 and analyzed with external tools for deep, customized analysis.

Cost Explorer is best for visualizations and basic analysis, while CUR is optimal for teams that need granular control, such as detailed billing and audits.

e) When to Use Each Tool

AWS Cost Explorer:

• Quick cost analysis.
• Setting budgets and forecasts.
• Savings recommendations.
• Custom alerts for simple monitoring.

AWS CUR:

• Detailed billing breakdowns.
• Custom analysis with external tools.
• Compliance and audits.
• Precise cost allocation by department, team, or project.

Note: CUR is ideal for detailed analysis and cost amortization.

Maintaining an efficient tagging system is crucial for both tools, but keeping consistency can be a challenge as operations scale or mergers occur. Without proper tagging, data can be inaccurate or of little use.

How Frust Uses These Tools to Generate Savings

Both tools are extremely useful for analyzing resource usage across your AWS infrastructure. Frust's integration with your infrastructure is exclusively financial through these services. They help us understand your consumption patterns, identify the most heavily used instance types and resources, and detect those that are oversized. This gives us a clearer picture of the cost structure of your infrastructure.