Windows or Mac only for the desktop version. The online version will work on any computer with a compatible web browser.
Here are the system requirements to install Turbo Tax for Windows…..
https://ttlc.intuit.com/community/system-requirements/help/minimum-system-requirements-for-turbotax-windows-software/00/26175
Here are the system requirements to install Turbo Tax for MAC…..
https://ttlc.intuit.com/community/system-requirements/help/minimum-system-requirements-for-turbotax-mac-software/00/25609
Online version system requirements
https://ttlc.intuit.com/community/system-requirements/help/turbotax-online-system-requirements/00/25787