How to Manage 4K Display Scaling in Windows 10

Now that high resolution displays are more affordable and prevalent than ever, it’s important to understand how to configure Windows to ensure the best experience at 4K resolutions and beyond. For years, traditional “standard resolution” displays were typically handled by Windows in a 1:1 ratio, with your PC’s video card providing one pixel of the actual user interface for every physical pixel on the display. This worked well for resolutions up to 2560×1600 on an adequately large monitor, but once you get into the 4K resolutions of today’s high-end monitors, a 1:1 pixel ratio — or 100 percent scaling, as Windows refers to it — produces an image that is unusable in most circumstances. The answer, therefore, is to make the user interface relatively large enough to be useable while still taking advantage of the millions of extra pixels available on high resolution monitors — something called display scaling in Windows (you may also recognize this basic idea from what Apple calls “Retina” resolutions). Here’s a quick look at display scaling in Windows 10.
First, let’s look at an example of why display scaling is needed in most cases when using a high resolution display with a Windows 10 PC. In our example, we’re using a 27-inch 4K monitor with a native resolution of 3840×2160. With 100 percent scaling — that is, a 1:1 pixel ratio — the Windows desktop and user interface appears tiny, and is likely too small for most users.

To fix this problem without giving up on our 4K monitor, we can adjust Windows 10 display scaling options in Settings. With your high resolution display connected to your PC, head to Settings > System > Display.

Here, you’ll see a slider labeled Change the size of text, apps, and other items. With compatible hardware, Windows 10 will attempt to automatically set this value to an appropriate percentage when connected to a high resolution display. However, you can manually adjust it by clicking and dragging the slider. Moving the slider to the left reduces the display scaling percentage, which will make things appear relatively smaller, while moving it to the right increases the display scaling percentage, making things look relatively larger.
In our example, we’ll move the slider to a value of 150 percent, which will give us a user interface with the same relative appearance as 2560×1440, which is a common and certainly workable resolution on a 27-inch display. To see how the math works out here, notice how 150 percent of 2560×1440 is exactly 3840×2160, our 4K monitor’s native resolution (2560*1.5 = 3840; 1440*1.5 = 2160).

If this scaled image is still too small, we can raise the Windows 10 display scaling percentage even higher. For example, a display scaling value of 200 percent would produce an image that is proportionate to 1080p resolution, or 1920×1080 (again, just check the math to see that 1920*2 = 3840 and 1080*2 = 2160).
The benefit of this configuration is that you end up with a user interface that is the same perceived size as the one you’re accustomed to, except that it’s noticeably sharper because each UI element is being drawn with four times as many pixels as a standard resolution display.
There’s no “correct” answer when it comes to display scaling percentage — the best percentage for each user will depend on the size and native resolution of their monitor, as well as their personal needs or preferences — so feel free to experiment with different values until you find a percent that you’re comfortable with. The only caveat is that you’ll need to log out each time you make a change. You’ll see some elements of the user interface change immediately as you adjust the slider, but Windows 10 requires a complete log out of your user account to switch everything over to the new scaling percentage.
Also note that Windows 10 display scaling isn’t limited to those with high resolution monitors. While the feature is certainly most useful on these large or pixel-dense displays, a user with even a standard resolution monitor can adjust display scaling, too, although raising the scaling percentage too much may make the Windows user interface comically large and unwieldy. If you have experience with OS X, this is similar to a Mac’s HiDPI Mode.