Why is my VS SDL 2.0 window 2x bigger than i specified?

I guess you solved the issue ages ago, but in case someone still has trouble with it: The issue is that Windows scales the window using the UI scaling setting (DPI scaling), as the program is flagged as non DPI aware. I had the same issue with my game on Steam. There are two ways to get Windows 8+ to not apply the scaling to your game: 1) right click on your compiled .exe select properties open the compatibility Tab select Change High DPI settings Tick the bottom box and choose: Override High DPI scaling behavior.

Scaling performed by: Application

This solution is inelegant and not suited for distribution, as you would need every user to do the same.

2. if using visual studio, set your manifest file to: DPI aware, monitor aware (and try to do the appropriate scaling in your program, or have options for the user to do so). To access the manifest, in Visual Studio 2013: Right Click on your target program in Solution Explorer, select: Configuration Properties\Manifest Tool Set DPI Awareness to: Per Monitor High DPI Aware, And Windows should leave your game alone.