The display is one of the most important interfaces between humans and machines, making information – quite literally – visible. The display of your computer can be a significant limiting factor for various reasons:
- it does not show you enough information
- it displays content inaccurately
- it strains your eyes
- its lack of image quality demotivates you
I have recently upgraded the desktop monitor for my home office and learned a few things that I would like to share. As someone who works in both Windows and macOS and is particular about image quality, I found it surprisingly difficult to find helpful information online. The topic that was the most vexing in my search was the question of the best monitor size and resolution because there was lots of conflicting information. How do you determine the ideal monitor size and resolution for your particular use case? In the following, I am going to focus on general productivity and image quality. I will not address gaming.
Summary
In general, if the monitor’s resolution is high enough (4K as a minimum), the scaling options in Windows and macOS work will allow you to customize the size of the workspace to one that fits your needs and looks good, although some monitor sizes at 4K resolution are better than others.
If you need a good monitor for productivity in both Windows and macOS and care about image quality, the best choices for a typical viewing distance between 60 to 80cm are:
- a 27-inch 4K monitor at 150% scaling or a same-sized 5K monitor at 200% scaling, both giving you a workspace of 2560×1440
- a 31.5 to 32-inch 4K monitor around 125% scaling or a 31.5 to 32-inch 6K monitor at 200% scaling, both giving you a workspace of around 3008×1692 in macOS and slightly more in Windows
- an ultrawide 34-inch monitor with 5120×2160 resolution, used at 150% scaling for a workspace of 3440×1440
For a viewing distance larger than 80cm, you may also find the following options acceptable:
- a 27-inch QHD (2560×1440) monitor without scaling
- an ultrawide 34-inch monitor (3440×1440) without scaling
It is difficult to recommend 24-inch monitors, at any of the common resolutions, if you use both Windows and macOS. If you really need a small monitor, good options would be:
- a 4K monitor between between 20 and 21.5 inches, scaled to 200% (1920×1080) if you can find one
- a 1920×1200 monitor (16:10) around the same size, used unscaled, giving you less sharpness but more workspace
If you are interested in finding out why these are good options, read on.
Monitor size
Assuming that the resolution is sufficiently high, a larger display is generally better for productivity because it will give you more digital space to work with. However, the largest feasible size is going to be determined by the space on your desk and by the distance between you and the screen. If you are sitting too close to the display relative to its size and need to move your head significantly to see the corners of the screen, this affects your ability to see everything and can lead to neck pain.
For the purpose of the following discussion, I will assume a typical viewing distance between 60 to 80cm. At this viewing distance, I would not recommend a desktop monitor below 27 inches. 27 inches are a good middle ground, not too large to be overwhelming but offering significantly more workspace than a 24-inch monitor. However, I have found that for me around 31.5 inches is actually ideal at this viewing distance, although it took some time to get used to at first. I would discourage anyone from buying a 24-inch monitor for reasons that are spelled out in more detail below. If you sit significantly farther away from your screen than 80cm, a size of 35 inches or more may be manageable.
By the way, a 34-inch ultrawide monitor (with an aspect ratio of 21:9) actually has the same height as a “normal” 16:9 27-inch monitor, but it is 34% wider. So, if you care more about horizontal than vertical workspace (e.g., because you work with timelines), this may be another good size to consider, assuming your desk is wide enough.
Resolution
A larger monitor size only makes sense if it means that its resolution is sufficiently high to also support a larger digital workspace. There is little point in upgrading from a 24-inch Full-HD monitor to a 27-inch Full-HD monitor because the larger display will only make things appear larger but not provide additional workspace – unless, of course, you need the elements to be shown larger because of poor eyesight or a long viewing distance.
In general, the higher the resolution the better because more pixels mean you can either display more information or have more scaling options to display the content at a size that works for you. However, in practical terms your options are limited by the output resolution of your computer’s GPU and its display connectors (DisplayPort and HDMI) support: the higher the resolution the higher the bandwidth that is required for the connection between your GPU and the display. For example, to drive a 4K Display at a 60Hz refresh rate, which is the minimum refresh rate you should aim for because anything else will look jarring, you will need a GPU that supports at least HDMI 2.0 or DisplayPort 1.2. While monitors with 5K resolution or above would be preferable at a monitor size of 27 inches and larger, as of this article (2022), support among Windows laptops is still spotty and there are also very few monitor options available. So, unless you use a recent MacBook Air or Pro, you will probably be limited to monitors with 4K resolution or less.
Common resolutions: The following table lists common resolutions and their total amounts of pixels which gives you an indication of the relative bandwidth needed for each. For example, 4K resolution displays four times as many pixels as Full HD and 8K resolution displays sixteen times as many.
| name | width | height | aspect ratio | pixels | factor |
| FHD | 1920 | 1080 | 16:9 | 2,073,600 | 1 |
| WUXGA | 1920 | 1200 | 16:10 | 2,304,000 | 1.111111111 |
| ultrawide FHD | 2560 | 1080 | 21:9 | 2,764,800 | 1.333333333 |
| QHD | 2560 | 1440 | 16:9 | 3,686,400 | 1.777777778 |
| WQXGA | 2560 | 1600 | 16:10 | 4,096,000 | 1.975308642 |
| WQXGA+ | 2800 | 1800 | 16:10 | 5,040,000 | 2.430555556 |
| ultrawide QHD | 3440 | 1440 | 21:9 | 4,953,600 | 2.388888889 |
| UHD (4K) | 3840 | 2160 | 16:9 | 8,294,400 | 4 |
| ultrawide 4K | 5120 | 2160 | 21:9 | 11,059,200 | 5.333333333 |
| 5K | 5120 | 2880 | 16:9 | 14,745,600 | 7.111111111 |
| 6K | 6016 | 3384 | 16:9 | 20,358,144 | 9.817777778 |
| 8K | 7680 | 4320 | 16:9 | 33,177,600 | 16 |
Pixel density
A display’s resolution alone does not tell us much. We need to know both monitor size and resolution to make sense of how much digital workspace we can realistically expect to be able to use. For this, you can refer to a display’s pixel density which is measured in ppi, pixels per inch.
Content that is displayed on a monitor with a higher ppi will look sharper. However, if the pixel density is too high, everything will look too small and you will need to use scaling. 4K on a 24-inch display does not give you the same digital workspace as 4K on a 32-inch monitor because you will need to use a higher degree of scaling to make text and other interface elements legible. You will likely not need to use scaling on a display with a ppi of 110 or less. In fact, macOS is designed for a pixel density of around 109 ppi and scales perfectly to double or thrice that (more on that below). In my opinion, the UI on Windows also looks just right at this pixel density. Any ppi that is significantly lower than 109 will make the user interface on macOS appear too large, and any that is higher will make it appear too small compared to Apple’s own devices. This holds true for the typical viewing distance we are talking about here; if you sit very far away you may in fact prefer a lower ppi.
However, depending on your viewing distance to the screen and your eyesight, a pixel density of 110 ppi or less is not necessarily ideal because individual pixels may be visible and text may not look smooth. The higher the ppi the more difficult it is to distinguish between individual pixels. Apple coined the term “retina” to refer to displays with a pixel density that is so high that the human eye can’t recognize individual pixels at a typical viewing distance. In fact, all recent iMacs and MacBook Pros have a pixel density of 218 ppi and higher which makes differentiating individual pixels impossible for most people even at viewing distances of less than 60cm. Depending on your viewing distance, however, you may not need a pixel density of 218 ppi.
“Given a large enough viewing distance, all displays eventually become ‘retina.’”
designcompaniesranked.com
A display with a ppi of 110 becomes ‘retina’ at a viewing distance of 32 inches or 81cm or more, so if you sit far away from your display, you may find it acceptable. Even so, the text will look sharper on a display with, say, 160 ppi, for reasons explained below. Because we defined a typical viewing distance as between 60 to 80cm, we should aim for a display that becomes ‘retina’ at around 60cm viewing distance. A display with a pixel density of 140 ppi becomes ‘retina’ at 61cm or more and would therefore be a preferable minimum for the viewing distance we are targeting – but you will need to use scaling.
Scaling in Windows 10 and 11
As of 2022, scaling works almost flawlessly in Windows 10 and 11. This used to be different some years ago when very little software was optimized for displays with high ppis, and interface elements or text would not appear correctly when scaling. Some apps that have not been updated may still look off, but I have not experienced any issues in common productivity apps recently.
What happens when you use a scaled resolution in Windows is that the monitor display will still run at its full native resolution, say, 4K, but user interface elements that use so-called “vector graphics” and text are recomputed with the additional pixels, making them appear larger without sacrificing sharpness. For photos and videos, which cannot be scaled up in this manner, there are two scenarios. When you open them individually, e.g., in an image editor or viewer, they will appear at their original size without scaling, so you are not sacrificing sharpness. However, if the photos or other non-scalable types of images, so-called “raster images” appear in a context, such as a website or an email, and with a pre-defined size, they may appear zoomed instead, making them appear larger at the cost of sharpness. Because many websites nowadays store multiple versions of the same image and serve the appropriate one depending on the resolution of your device, this is mostly not an issue, however. My experience of scaling anywhere between 125% and 200% on 4K displays in Windows 10 has generally been excellent.
Scaling in macOS
Scaling in macOS is a bit more complicated. Any resolution that is scaled (more than 100%) is rendered at twice the resolution off screen and then scaled down to the native resolution of the display. For example, 150% scaling on a 4K display will look like 2560×1440 (QHD), but the actual resolution rendered by macOS is 5120×2880 (5K) and then scaled down to fit the 4K screen (3840×2160). This is why macOS tells you that using any scaled resolution may affect performance: because your Mac will need to compute significantly more pixels than at native resolution. The benefit of this approach is that individual apps do not need to be optimized for different scaling factors – they just need to work well at 100% or 109 ppi. MacOS takes care of the scaling and thereby ensures that text will always be displayed at a consistent size across all apps. I assume that it is also easier to scale down than it is to scale up because you have more available virtual pixels to work with and lose less sharpness.
Because macOS uses integer scaling, i.e., scaling only at whole numbers like 1x, 2x, etc., image quality is best on displays with a ppi of around 109 ppi or a multiple of that (218, 327 or 438). That is why desktop Macs and Apple branded desktop monitors generally have a ppi of around 218 and use 200% scaling as default: so that the rendered resolution matches the native resolution of the display and there is no downscaling involved. When there is downscaling, pixels rendered off-screen may not perfectly match the pixels on screen, which may in turn make intricate shapes such as text appear slightly less sharp. That is why scaled resolutions have a bad reputation among macOS purists.
Pixel density for various monitor sizes and resolutions: The following chart shows you which resolution is right for which monitor size if you only want to use integer scaling (100%, 200%, 300%, etc.). Pixel densities that are close to 109 ppi (or multiples of that) are marked in green.
| monitor size: | 20 | 21.5 | 24 | 25 | 27 | 28 | 30 | 31.5 | 32 | 34 | 35 | 38 | 40 |
| 1920×1080 | 110.1 | 102.5 | 91.8 | 88.1 | 81.6 | 78.7 | 73.4 | 69.9 | 68.8 | 64.8 | 62.9 | 58.0 | 55.1 |
| 1920×1200 | 113.2 | 105.3 | 94.3 | 90.6 | 83.9 | 80.9 | 75.5 | 71.9 | 70.8 | 66.6 | 64.7 | 59.6 | 56.6 |
| 2560×1080 | 138.9 | 129.2 | 115.8 | 111.1 | 102.9 | 99.2 | 92.6 | 88.2 | 86.8 | 81.7 | 79.4 | 73.1 | 69.5 |
| 2560×1440 | 146.9 | 136.6 | 122.4 | 117.5 | 108.8 | 104.9 | 97.9 | 93.2 | 91.8 | 86.4 | 83.9 | 77.3 | 73.4 |
| 3440×1440 | 186.5 | 173.5 | 155.4 | 149.2 | 138.1 | 133.2 | 124.3 | 118.4 | 116.5 | 109.7 | 106.5 | 98.1 | 93.2 |
| 3840×2160 | 220.3 | 204.9 | 183.6 | 176.2 | 163.2 | 157.4 | 146.9 | 139.9 | 137.7 | 129.6 | 125.9 | 115.9 | 110.1 |
| 5120×2160 | 277.8 | 258.5 | 231.5 | 222.3 | 205.8 | 198.5 | 185.2 | 176.4 | 173.7 | 163.4 | 158.8 | 146.2 | 138.9 |
| 5120×2880 | 293.7 | 273.2 | 244.8 | 235.0 | 217.6 | 209.8 | 195.8 | 186.5 | 183.6 | 172.8 | 167.8 | 154.6 | 146.9 |
| 6016×3384 | 345.1 | 321.0 | 287.6 | 276.1 | 255.6 | 246.5 | 230.1 | 219.1 | 215.7 | 203.0 | 197.2 | 181.6 | 172.6 |
| 7680×4320 | 440.6 | 409.8 | 367.2 | 352.5 | 326.4 | 314.7 | 293.7 | 279.7 | 275.4 | 259.2 | 251.8 | 231.9 | 220.3 |
Scaling on Apple’s own devices
In a perfect world, we would only be using displays that have the right pixel density for integer scaling. However, in practice, bandwidth and other hardware limitations in GPUs and displays mean that this is not always feasible. In fact, even some of Apple’s most popular devices use up- and downscaling per default in order to give users more available workspace.
Table: Scaling factors that are not integers are marked in red.
| model | screen size (inch) | UI width | UI height | resolution width | resolution height | scaling factor |
| iPhone 6/7/8/SE 2 | 4.7 | 375 | 667 | 750 | 1334 | 2.0 |
| iPhone 12/13 mini | 5.42 | 375 | 812 | 1080 | 2340 | 2.9 |
| iPhone 12/13 | 6.06 | 390 | 844 | 1170 | 2532 | 3.0 |
| iPhone 8 Plus | 5.5 | 414 | 736 | 1080 | 1920 | 2.6 |
| MacBook (2015 or later) | 12 | 1280 | 800 | 2304 | 1440 | 1.8 |
| 13-inch MacBook Pro (Intel)/MacBook Air (2018 or later) | 13.3 | 1440 | 900 | 2560 | 1600 | 1.8 |
| MacBook Air (before 2018) | 13.3 | 1440 | 900 | 1440 | 900 | 1.0 |
| 14-inch MacBook Pro (Apple Silicon) | 14.2 | 1512 | 982 | 3024 | 1964 | 2.0 |
| 15-inch MacBook Pro (Intel) | 15.4 | 1680 | 1050 | 2880 | 1800 | 1.7 |
| 16-inch MacBook Pro (Apple Silicon) | 16.2 | 1728 | 1117 | 3456 | 2234 | 2.0 |
| 27-inch iMac (Intel)/Apple Studio Display | 27 | 2560 | 1440 | 5120 | 2880 | 2.0 |
| Apple Pro Display XDR | 32 | 3008 | 1692 | 6016 | 3384 | 2.0 |
Even though the displays of the iPhone 12 mini and 13 mini or the 13- and 15-inch MacBook Pros use de-facto scaling factors that are less than 3x or 2x, image quality is generally excellent based on my own experience. I would therefore question the need to adhere strictly to monitors with a ppi of 109 or 218.
The best monitor sizes for 4K resolution
Now that we have established that it is common practice even for Apple’s own devices to not scale perfectly at 2x or 3x, let’s look at the options you have for scaling in macOS and Windows 10 when using a 4K display – which is the most readily available resolution at a large range of monitor sizes.
Table: Scaling options in Windows and macOS. The resolutions in brackets indicate the available workspace.
| Windows | macOS |
| 100% (3840×2160) | 100% (3840×2160) |
| – | 114% (3360×1890) |
| 125% (3072×1728) | 128% (3008×1692) |
| 150% (2560×1440) | 150% (2560×1440) |
| 175% (2194×1234) | – |
| 200% (1920×1080) | 200% (1920×1080) |
Chart: The following chart illustrates the pixel density (ppi) at 4K resolution for various monitor sizes. The green areas mark the ppi ranges that are good for a certain scaling option in macOS, assuming an ideal ppi of 109 and allowing for a deviation of up to 5.
You will notice that the only common 4K monitor sizes that come close to the targeted ppi are 20 inches (for 200% scaling), 27 inches (for 150% scaling), 31.5 or 32 inches (for around 125% scaling), and 40 inches (at non-scaled resolution). The latter would, however, not be ‘retina’ at a viewing distance of less than 80cm. Therefore, the ideal ‘retina’ 4K monitor size at our targeted viewing distance would be close to either 27 or 31.5 inches for a single desktop monitor setup or close to 20 inches for a very small desk or a dual desktop monitor setup.
Of course, if you do not care whether UI elements in macOS are shown at their intended size similar to how they would look on your MacBook, or if for whatever reason you actually want elements to be displayed larger than usual, the above considerations may be less important. However, I would maintain that you should aim for a monitor with a ppi of around 140 or above if your viewing distance is less than 80cm.
Conclusion
The takeaway is that if the monitor’s resolution is high enough (4K as a minimum), the scaling options in Windows and macOS work will likely allow you to customize the size of the workspace to one that fits your needs and looks good. Especially text will benefit from monitors with high pixel density (140 ppi and larger, used at scaled resolutions). If both your Mac and your Windows PC support 5K or 6K output and money is not a concern, monitors with these resolutions, such as those sold by Apple, will provide even sharper text (but not more workspace!). Here is hoping that a larger range of 5K and 6K monitor options at various price points will appear in the next years. If you care about cost-performance, you will likely be happy with a 4K display at the sizes recommended above. I certainly am.
Monitor size, resolution and pixel density are of course only some of the factors to consider when choosing a desktop monitor. However, because they will determine your available digital workspace, they are arguably the most important for productivity. If you care about image quality, other factors you should consider are color space support and color accuracy as well as backlight uniformity. Ergonomics, especially the monitor stand, are another factor to consider for a productivity monitor, although you can always purchase a third-party stand or monitor arm if the monitor supports a VESA mount.
References
- You can access the spreadsheet that I used for all calculations and graphs in this article via Google Sheets here
- List of resolutions for all iOS devices: https://www.ios-resolution.com
- List of Apple’s retina Macs and displays: https://support.apple.com/en-us/HT202471
- Interesting YouTube video by Fact Check that addresses additional factors to consider when choosing a monitor size
- Information on retina viewing distance: https://www.designcompaniesranked.com/resources/is-this-retina/
- Recommended website for information on consumer monitors: https://www.displayninja.com/
(all sources were last accessed on May 6, 2022)
Other fun facts
So what monitor did you buy? I ended up buying an Eizo Flexscan EV3285, which is a 31.5-inch 4K productivity monitor. Although it does not support a wide color space, it has been confirmed by review sites as having excellent color accuracy for sRGB and backlight uniformity. When I compared it with other desktop monitors available in a specialist store in Akihabara (Tsukumo), the picture appeared considerably clearer and calmer than monitors sold by LG et al., more like looking through a clean window rather than looking at a flickering screen. On many of the monitors advertised as supporting HDR and wide color gamut, colors actually looked worse in my subjective opinion. Eizo also has a reputation for providing very good customer support (at least in Japan) and offers a five-year warranty. However, their products are considerably more expensive than those of competitors. The same Eizo Flexscan range also includes a 27-inch 4K model that should be just as good in terms of picture quality, the EV2785.
Inches? The size of a display is customarily indicated in inches (e.g., 27 inches), even in countries, such as Germany, that do not generally use inches (or “Zoll” in German) to measure length. The number refers to the length of the diagonal of the monitor, that is, the distance between the two most distant points of the display (e.g., lower-left corner to upper-right corner). If you know the aspect ratio, that is, the ratio between the width and height of the display (e.g., 16:9), you can calculate the width and height of the display with Pythagoras’ theorem.
How to calculate pixel density? You get the pixel density in ppi by dividing the pixels on one dimension of the display by the length of the monitor in inches on that same dimension. However, monitor sizes generally refer only to the diagonal and not to the width or height. You therefore need to calculate the pixels on the diagonal to then divide it by the monitor size. Or you could calculate the monitor’s width or height in inches if you know its aspect ratio. You can use Pythagoras’ theorem in both cases. Alternatively, you can use an online ppi and retina distance calculator such as this one by designcompaniesranked.com.
Why is the pixel density of 4K not four times that of FHD? Because pixel density is measured only on one axis (in inches instead of square inches), a display with a pixel density that is twice as high actually has four times as many pixels (twice as many in width and twice as many in height). Conversely, a Full HD display has half the ppi as a 4K display of the same size but only one-fourth of its pixels.
Excellent write-up! I went through a similar research process when I bought my 27in 4K monitor a couple of years ago.