the cost of Individual EC2 Instance

Pricing is different depending on the region you are using, and if you are bringing your own Windows License or not.

Please use the AWS Pricing Calculator to find out what it would cost in the region in which you want to run it, and enter the licensing choices you would like.

https://calculator.aws/#/createCalculator/EC2WinSQL

Use aws estimate calculator https://calculator.aws/#/

If you have any cost allocation tag on the instance, you can look at Cost Explorer using the tag as the filter. https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/cost-alloc-tags.html

You can try to use the Calculator in this case is https://calculator.aws/#/addService/ec2-enhancement

Please note that the price of an EC2 instance will include

• Running hours (on-demand)
• EBS volume
• EIP (If any)
• Detail monitoring (If any)
• Data transfer (if any)
• CloudWatch (If any)

What are you trying to do? Is it setting up a MS SQL Server for test or production? I would suggest to consider RDS especially if you want to concentrate on your project and leave the maintenance and management of the database to Amazon.