Yes, you can use AutoCAD on both Mac and Windows if you are on an AutoCAD subscription. You can use the same subscription username and password to activate your software on either Windows or Mac platforms. The version years must match, and you'll need to download and install the correct software for your operating system. (If you download a free trial of AutoCAD and want to try it on both platforms, you need to sign up for 2 trials, one for Windows and one for Mac. You can choose to download and try each version simultaneously or one after the other. Note that the AutoCAD mobile app isn't a part of the trial, but is included in the subscription).