For most people monitor pixel density does not matter, it is an important factor for image and design professionals. For the layman, the average computer user with a normal desktop setup (which is very common), monitor pixel density probably makes no difference to your daily computing life – so why learn the technical jargon?
Well, sometimes knowing certain terms can give you insight into what we do and how we think about our interests and hobbies. Being able to talk and understand terminology is often a good thing if you find yourself in a position where someone asks "so what's this monitor resolution I keep reading about?" or similar questions.
Even if they don't ask those kinds of things out loud, having those concepts in mind even if only as mental notes may prove useful in the future.
What is PPI?
Pixels per inch or PPI is a term used to describe pixel density – dots per inch or DPI. This might be a little confusing because the acronym PPI actually stands for something else (it's typically used to refer to printer paper sizes like 8.5x11).
Most monitors are referred to using diagonal length (ie, what size they would be if you measured them from corner to corner) in inches. Then, for example, someone might say "this monitor has 178 pixels per inch" which means that there are 178 dots of information spread across every square inch on the screen (what appears as one square inch on your monitor will contain more than 178 separate 'dots' of color information).
If you think about it this makes sense; PPI is a general term for how dense the pixels are. The more dots of information there are per inch, the denser the pixel density.
A few examples of monitor resolutions that you might encounter:
1920x1080, 1680x1050, 1366x768 – common screen resolutions for a variety of monitor sizes and aspect ratios.
2560x1440 – a higher pixel density used by people who want more pixels on their screens. A 27" 2560x1440 monitor is about the same as having two 1080p monitors next to each other (or one 1440p monitor).
1680x1050 vs 1920x1080 – probably the most common question asked by those not familiar with terms related to a computer display. The difference between these two resolutions is often considered insignificant or barely noticeable. However, it does look different due to the increased pixel density (the 1920 monitor has more pixels).
A side note: if you're interested in this kind of information, read up on terms like pixel pitch, horizontal and vertical PPI, aspect ratio. If you wanted to be thorough, it's also worth doing some research about color profiles (RGB vs CMYK) and other relevant computer display terms.
If there are any words or phrases that you feel like you should know but don't know what they mean then definitely search for them!
What does monitor PPI have to do with computer programming?
Although many people can be satisfied by using monitors with mediocre pixel density (ie, 1920x1080 on a 24" monitor or 1080p on a 27-32"), some people want and need as many pixels as possible on their screen(s). To give you an idea:
1920x1080 on a 24" monitor = 92 DPI, 1080p on 27-32" = ~110 DPI
2560x1440 on 27" = 110-114 DPI
The difference between these kinds of resolutions is very noticeable and is one of the primary reasons why some programmers prefer to use higher DPI monitors.
Many programmers swear by 160 or even 200+ DPI on their second monitor because they want as much information on the screen as possible without having to squint. The improvement in readability can be drastic if you work with code all day (this also depends on personal preference, your eyesight, your glasses/contacts prescription, etc).
Do you need the highest pixel density?
It is not always better to have the highest pixel density (most pixels per inch) possible. There are three main things to consider.
Your physical screen size, type of monitor (TN or IPS), and distance from it. Do you want more information on your screen? If not, then having a higher DPI is probably not necessary for you.
Your hardware limitations – you might experience eyestrain if your computer does not have enough processing power to drive the extra pixels (although this will only be an issue if you're spending several hundred dollars or more on a high-DPI monitor).
It's also very likely that your graphics card will be unable to handle rendering everything at full resolution; in which case it would be better to use one with a lower DPI but the same number of total pixels.
How useful are the extra pixels?
If you're not using a second monitor then having a higher PPI is probably not very beneficial for you, since it will be more likely that you'll have to scroll horizontally or use other techniques to view more information on your screen.
If you want maximum pixel density, then it's best that the resolution of your main monitor matches the DPI of the second one(s). For example, if you have two 2560x1440 monitors side-by-side, there are 9 "rows" of horizontal pixels in each monitor so this means that both 2880 x 1440 = 25600 total horizontal pixels for both monitors.
Divide this by 1440 and convert it into DPI (25600 ÷ 1440) to get 160 DPI (not taking into account the 1/16th fixed pixels that can't be changed).
There are other types of secondary monitors, however, which you might find better for your workflow. For example: if you use tmux, several people claim that splitting the same window vertically between two different screens has a nice clean look and is very useful, particularly if you work on multiple things at once.
There are also wide-screen aspect ratio monitors with high pixel densities available so they can be very useful for programmers who like working in IDE's such as vscode.
What is 'Retina'?
If you are looking for a high DPI monitor, make sure to look for one that says 'Retina' somewhere on the box. It is very important that while buying one you take into account your eyesight and adjust your distance accordingly.
Do not buy a monitor with a pixel density higher than your eyes can handle! If you do so, it will be painfully bad for your vision! At least get an eye exam once in 1-2 years just to check what kind of effect it has on you after prolonged use.
The retina display standard was developed by Apple because many people have become near-sighted due to all the screen time they get each day. I'm sure there are other companies out there making monitors with retina standards but these are likely to cost even more than the 'retina' ones.
Getting used to a high DPI monitor If you switch from using a standard resolution monitor (Sri) to a higher-DPI one (HD), then as with any change it will take time for your eyes and brain to adjust; give yourself at least two weeks of regular use before judging whether you like the increase in screen real estate or not.
You don't have to stare directly at the center of the screen all day – move your eyes around and rest them every now and again, just as you would when reading a book for instance! More information on reducing eyestrain.
Optimal viewing distance
The recommended viewing distance is generally known to be around an arm's length (around 1.5 meters away).
There are however some studies that claim the optimum DPI and screen size will vary depending on age: teenagers should have a lower pixel density than young adults, for example. Other people say that if you're using a laptop then it would be better to have a higher resolution but sit closer since laptops generate more heat compared to their larger counterparts with the same specs.
In any case, your eyes will not adjust well unless you give them enough time – so do not sit uncomfortably close thinking it's going to correct itself!
If your eyes start feeling tired after an hour or so then it would be best to look away from the screen for a few minutes every now and again. You could set up an alarm perhaps that reminds you to take short breaks (just as you can with phone apps).
Adjusting text size
You might notice the text on your computer looks really small, but don't fret! Mac OSX has a built-in system-wide way to make it much larger called "system preferences/display/adjust font size" where you can adjust it by 10% increments up to 500%. If this is not enough for some reason, there are plenty of other options available.
If your text looks blurry or you want to remove jagged edges from fonts, Mac OSX has an option called "anti-alias" which can be accessed through the system preferences/fonts where there are two options: 'best for appearance' and 'best for readability'.
What pixel density is better for gaming?
As with any relatively recent computer, it will depend on the game you are playing. As a general rule of thumb though, if your screen is smaller or has fewer pixels per inch then you can aim for a higher frame rate whereas having more pixels means that you would be able to run it in higher detail at the same frame rate.
This being said, some people have better eyesight than others so they would prefer more clarity when looking at lots of small objects rather than just having everything move faster around them!
Many laptops come with an option to switch between integrated graphics and discrete ones where the latter will allow you to play games but only with lower settings. There are also laptop manufacturers who offer different pixel densities across their range so check to see what your favorite brands offer!
What pixel density is better for work?
Adobe recommends that you have at least 120 PPI for any text-based work (such as writing and coding) and 150 PPI for diagrams and schematics. If your resolution is set to anything below this then you can expect increased eyestrain while also wondering why the information on the screen seems so small.
If however, you are doing something like photo or video editing where precision matters more, then it might be better to add a few more pixels per inch (PPI).
As with anything, more expensive screens will tend to have higher pixel density whereas cheaper ones are usually on the lower end. If you are looking for a screen for some kind of design work then it would be best to check out professional reviews on reliable websites since there will be lots of factors that influence which technology works best in your particular case!
Conclusion
Monitor pixel density is the number of pixels per inch on a monitor. High-resolution monitors have more pixels per inch, so the text will be sharp and clear. Higher pixel density is especially important for people who do graphic design work or video editing where there are lots of small objects displayed on the screen.
Lower pixel density means that your computer needs to use software tricks like scaling when displaying images in order to make them look normal when viewed from a distance (called up-scaling). If you set your screen's resolution too low then not only can it become quite blurry but also difficult to see!
Therefore, higher pixel density allows for sharper text and clearer graphics near the edges while lower pixel density makes everything larger and easier to see further away due to software up-scaling.
Now that you know what monitor pixel density is, go ahead and check your current monitor's pixel density. If it is not as high as you would like, consider buying a higher resolution display to make everything easier to read!