If you are sticking with Windows 7, is the final stable release that offers full, native compatibility. It remains a robust tool for professional-grade schematic capture and PCB layout.
Even as an older version, it includes the 3D viewer, Push-and-Shove router, and extensive component libraries.
Most Windows 7 machines are 64-bit; look for the x86_64 installer (approx. 1.2 GB). Kicad For Windows 7
Completely free with no subscription or "lite" version limitations.
While the latest versions of KiCad have moved toward supporting modern operating systems, it is still possible to run this powerful, open-source PCB design suite on Windows 7. The Compatibility Gap If you are sticking with Windows 7, is
Right-click the installer and select "Run as Administrator" to ensure it has the permissions to register system DLLs.
Projects created in 5.1 can be opened in newer versions later if you eventually upgrade your OS. Most Windows 7 machines are 64-bit; look for
Massive library of tutorials and forum posts specifically for the 5.1 interface.