Why are windows different sizes on screens with the same resolution?

Solution 1:

Assuming that both of those screens are properly set at 1920x1080.

The same sized window on a 15.6in screen like on your laptop and on a 21.5in will be different even if the resolution is the same because the size of the screens differs. The window will be 37.8% larger on the 21.5in screen than on the 15.6in screen.

For the window to be the same size on both screens, either they must be the same size and resolution, or they must have the same pixel density. Neither is true with these two screens.

To fix this, one needs to set the resolution of the 21.5in screen to 2646x1488. Or reduce the resolution of the 15.6in screen to 1393x783. Or move the 21.5in further away from the user.

Solution 2:

The monitor supports custom scaling (page 22 of the manual). Check the setting with your OSD (on screen display) as it is possible this setting is causing the image to appear larger than you expect.

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