Citations

Special thanks to Frank Contrepois on completing the original RHEL analysis which forms this blog post, his further detailed research can be found here.
 

Introduction

This article delves into the pricing structure of Windows licenses on AWS, aiming to provide insights into how the costs of Windows licenses are determined and identify the factors that influence price variations. We will explore the data and methodology used to analyze the pricing, examine the extraction of Windows license prices, and discuss the findings. We will explore the data and methodology used to analyze the pricing, examine the extraction of Windows license prices, and discuss the findings.

Key Takeaways:

1. Fixed Windows License Cost: Regardless of factors such as CPU, normalization factor, or region, the price of a Windows license on AWS remains consistent at $0.046 per hour per vCPU. This fixed cost applies to the majority of instances, with only a few exceptions.
2. Limited Price Variation: The analysis reveals that the calculated Windows license price per vCPU is concentrated between $0.045 and $0.047, accounting for approximately 95% of the data. This consistency suggests a high level of accuracy in pricing approximation.
3. Exception Instances: Some instance families, such as the “t” family and certain older instances, deviate from the standard Windows license pricing structure. These exceptions are attributed to different licensing agreements or configuration errors and should be considered separately when budgeting for Windows licenses on AWS.

Understanding the Data and Methodology

The data used in this analysis is from April 2023 and was obtained through AWS CodeBuild scripts that utilized the AWS Bulk API to download the pricing data. The data was then filtered to focus on Windows licenses, allowing for further investigation and analysis.

Extracting the License Price

Unlike Linux, which is free, a Windows license incurs an additional cost on top of the VM price. To determine the cost of a Windows license, the price of a Windows VM is compared to the price of a Linux VM. The difference between these two prices represents the Windows license cost. It’s important to note that this calculation considers the simplest version of an instance type without any additional software.

Exploring Factors Affecting License Prices

Understanding the License Price

Windows licenses on AWS are priced at $0.046 per hour per virtual CPU (vCPU). This pricing model has remained consistent, with 95% of the calculated Windows license prices falling between the range of $0.045 and $0.047 per vCPU. This aligns with the findings from previous analyses conducted in 2020, where the cost was determined to be $0.046 per hour per vCPU.

Licensing Options

On Amazon EC2, customers can choose to run instances that include the relevant license fees (“license included”) or utilize licenses they have already purchased from Microsoft (“bring your own license” or BYOL). Windows Server and SQL Server licenses can be included in the cost of EC2 instances, while other Microsoft software requires customers to bring their own licenses, subject to Microsoft’s terms.

Exceptions to Windows License Pricing

There are some exceptions to the standard Windows license pricing. The “t” family instances and certain old instances, mistakenly listed as current generation instances, have different licensing agreements and are not priced at $0.046 per hour per vCPU. These exceptions are further explored in the accompanying graphs.
 

Conclusion And Final Thoughts

In conclusion, the pricing structure for Windows licenses on AWS can be summarized as follows:

• Windows licenses on AWS are priced at $0.046 per hour per vCPU in most cases.
• The “t” family instances and certain old instances have different licensing agreements and are not priced at $0.046 per hour per vCPU.
• The majority of Windows license prices fall within the range of $0.045 and $0.047 per vCPU.
• These findings provide valuable insights for users seeking to understand and budget for Windows license costs on AWS.