ClearType FAQ

On Windows XP:

NOTE: If you install Windows XP yourself, by either upgrading an existing Windows installation or performing a fresh install, ClearType will be turned off by default. Computer manufacturers that pre-install Windows XP have the option of turning it on or off by default.

You can also turn ClearType on using our ClearType Web interface or downloadable PowerToy Tuner. These allow you to tune ClearType for your own personal preference and for your display. Tuning ClearType makes an adjustment to Windows XP's 'contrast' or 'gamma' value set for your screen. For more information on gamma, see this page.

ClearType is a form of sub-pixel font rendering that draws text using a pixel's red-green-blue (RGB) components separately instead of using the entire pixel. When the pixel is used in this way, horizontal resolution theoretically increases 300 percent.

Picture elements on an LCD screen are actually comprised of individual horizontally-oriented red, green and blue sub-pixels. For instance, an LCD screen that has a display resolution of 800x600 pixels actually has 2400x600 individual sub-pixels. The human eye is not capable of differentiating colors on such a small scale, so a combination of these three primary colors can emulate any intermediate color. Sub-pixel font rendering takes advantage of this by antialiasing at the sub-pixel level instead of at the pixel level.

For more information, see our What is ClearType page. For a technical overview of how ClearType works, see this Microsoft research paper written by John Platt.

No two screens are exactly the same and everyone perceives color in a slightly different way. For these reasons, we recommend that Windows XP users visit our ClearType Web interface or downloadable PowerToy Tuner.

To see if your screen is set to its native resolution, try looking at the following eye test image. The image is made up of many vertical black lines. If you see alternating bands of white running vertically through this image, you are probably running at a non-native resolution.

This page has more information on how to set your screen resolution.

Yes. A minimum setting of Medium (16-bit) color quality is required to display ClearType. To check or adjust your color settings, use the Settings tab of your Display Properties control panel.

Yes. Settings are saved for each user account.

No. You cannot have different settings for each monitor in a multiple-monitor setup or when docking a laptop.

ClearType works best on color LCD screens, but there are various things to check depending on the type of screen you are using:

Yes, but less so than with LCD displays. Because a standard cathode-ray tube (CRT) screen uses an electron beam to activate pixels, ClearType does not provide the same benefits that you experience on an LCD screen. However, because ClearType still applies a form of filtering similar to traditional antialiasing, you may see some improvement when enabling ClearType on a CRT screen.

It depends. Most LCD screens have a RGB striping order. A very small number have a striping order of BGR. The image below shows side-by-side examples of text rendered with RGB or BGR ordering. If the BGR example looks better on your screen, then your screen may be using a BGR striping order.

Support for BGR displays was added to Windows XP with Windows XP Service Pack 1 (SP1).

Type designers can license our Visual TrueType (VTT) font hinting tool. VTT was updated to let designers proof their fonts under ClearType. Information on licensing VTT can be found here.

Yes. In May 2001, Microsoft received its first ClearType patents from the U.S. Patent and Trademark Office. Other patent applications are pending. Developers looking to license Microsoft ClearType patents should visit our ClearType patent licensing site.

No.