Text clarity is often an overlooked aspect for a lot of people when purchasing a monitor, since we're often focused on how well it performs for gaming or how well it performs in a bright room setting. However, considering that nearly all online content has some form of text, it's important to be able to read comfortably and not have to guess what a particular letter is. Of course, aside from resolution and pixel density, how clear a text looks is subjective. We judge text clarity under normal viewing conditions as well as using a close-up photo, and we look at how well it handles sub-pixel rendering techniques like Windows ClearType.
Since text clarity is mostly a subjective test, we only make use of a computer running on Windows 10, connected to the monitor that is being tested. The monitor's brightness is set to 100 nits using a checkerboard pattern as our reference, and we leave most settings at its default state, such as sharpness, resolution, and scaling. Photos are taken with and without ClearType, which are then subjectively scored.
When it comes to our scoring for text clarity, we follow a few general guidelines, but the score is still subjective. Pixel density is the first thing that we judge, as it's a quantifiable aspect of the monitor; a higher resolution on a smaller display will produce a sharper-looking text with less jagged lines. Then, we judge the legibility of the text subjectively; the easier it is to read, the higher it scores. Lastly, we compare it to other monitors that we've reviewed and adjust the score accordingly. We also subjectively score how ClearType affects text clarity, as it doesn't always behave the same way depending on the panel type and sub-pixel layout of the monitor.
Windows users have access to ClearType, which is a feature that enables the sub-pixels to be controlled individually when rendering text, independent of the entire RGB pixel. This effectively triples the monitor's horizontal resolution when rendering text. Generally speaking, ClearType does a fairly good job at sharpening text and it's more noticeable on lower resolution displays, but it can also make the edges of a letter look more blurry, like an anti-aliasing effect. On VA panels, ClearType can make text look blocky and jagged, and displays with a BGR sub-pixel layout can also behave strangely, even though Windows has built-in support for this type of display. In this photo, we're looking at how well-defined the letters are, especially diagonal lines like the ones on the 'R' and 'N' in the photo of the Acer Nitro XV273X.
In the photo with ClearType off, we're again looking at how defined the letters are. The diagonal line on the 'R' looks more jagged and the one on the 'N' is barely visible. Without sub-pixel rendering, the entire pixel at the edge of a letter is lit, creating a shadow effect and making letters like 'T' and 'I' look uneven.
The majority of monitors on the market have an RGB sub-pixel layout, but some use a BGR layout, like the Philips Momentum 436M6VBPAB, where the red and blue sub-pixels are reversed. This type of layout isn't bad in and of itself, as it isn't noticeable when displaying an image, but it does affect text rendering, especially if you want to enable ClearType. Text on monitors with a BGR sub-pixel layout often look thin and jagged with ClearType on, but it isn't consistent, so some lines will appear fine while others don't. Other types of sub-pixel layouts can also affect text clarity, such as RGBW, although it's a layout that we see more often on TVs than on monitors, which you can read about it here. Also, a panel's coating can affect text clarity, which is why the photo above of the Acer Nitro XV273X looks a bit blurry, since it has a matte anti-reflective coating.
If you want to use ClearType to improve text clarity, type in 'Cleartype' in the Windows search bar and choose the option 'Adjust ClearType text.' You'll then be prompted to go through a five-step tuning guide where you have to choose the box that looks best to you. On the first test where there are only two options, although it isn't clearly stated, the left choice is for monitors with an RGB sub-pixel layout, while the right one is for a BGR layout. Afterward, complete the tuning as directed. As always, features like ClearType are a matter of taste and some people may find it bothersome on some monitors, so you should adjust it to your preference. If you don't get the desired result, the tuning can always be performed again or you can disable it completely.
While we often focus on picture quality or how low the input lag is, text clarity is an important aspect to consider when purchasing a monitor since most of us use them for multiple purposes. The general rule of thumb is that the higher the pixel density a monitor has, the sharper the text will look, even if you don't use ClearType. Also, keep in mind that ClearType only affects text, not text within an image.