The Ultimate Guide to Understanding the Cost of Windows 11

I've been checking around on multiple sites about how much Windows 11 is. I need to activate multiple computers and I don't want to have to buy them directly from Microsoft because that's a rip off. From what I've read there is a difference between OEM keys and Retail keys. Multiple sources are saying to avoid OEM keys as they often get deactivated. They aren't intended for distribution and are generated by the manufactures of computers that come with Windows already installed.