Official specs from Steam

Forza Horizon 4 system requirements

Minimum and recommended PC specs as listed by the developer on Steam.

Forza Horizon 4 release infoSteam page Check other games

Minimum

NoteRequires a 64-bit processor and operating system
OSWindows 10 version 15063.0 or higher
ProcessorIntel i3-4170 @ 3.7Ghz OR Intel i5 750 @ 2.67Ghz
Memory8 GB RAM
GraphicsNVidia 650TI OR AMD R7 250x
DirectXVersion 12
NetworkBroadband Internet connection
Storage80 GB available space

Recommended

NoteRequires a 64-bit processor and operating system
OSWindows 10 version 15063.0 or higher
ProcessorIntel i7-3820 @ 3.6Ghz
Memory12 GB RAM
GraphicsNVidia GTX 970 OR NVidia GTX 1060 3GB OR AMD R9 290x OR AMD RX 470
DirectXVersion 12
NetworkBroadband Internet connection
Storage100 GB available space

FAQ

What graphics card do I need for Forza Horizon 4?

Minimum: NVidia 650TI OR AMD R7 250x. Recommended: NVidia GTX 970 OR NVidia GTX 1060 3GB OR AMD R9 290x OR AMD RX 470.

How much RAM does Forza Horizon 4 need?

Forza Horizon 4 needs 8 GB RAM at minimum, 12 GB RAM recommended.

How big is Forza Horizon 4?

Forza Horizon 4 requires 80 GB available space.

Does Forza Horizon 4 run on Mac or Steam Deck/Linux?

There is no native macOS version. There is no native Linux build (Proton compatibility may vary).