Screen resolution is one of the key factors that is considered when purchasing a display unit. Today all monitors come in the High Definition range which starts from 720p and goes up to 8K (4320p). Here we will go into an understanding of what screen resolution is and other important terminologies. Then we will compare these resolution based on their refresh rate, response time and pixel density.
What is Screen Resolution
Before looking into all the different resolutions we must have a basic understanding of what it means. Screen Resolution is the measure of pixels in an image. For example, whenever a display is said to be 720 pixels, it refers to the pixel height of an image in a 16:9 (length x height) aspect ratio. Therefore, a 720p display is actually 1280×720 resolution and 1080p is 1920×1080.
4K is a screen resolution format that is named so for a specific reason. If it follows the pixel height rule then it would represent 2160p and many still call it so for ease of understanding. It is called 4k because you could fit four 1920x1080p images in a single 3840×2160 image. Another variation of this is DCI 4K which has a width of 4096 pixels.
When purchasing a display you should aim for the highest resolution you can afford. The higher the resolution the sharper your image would be. Features like colour reproduction and aliasing improve much fold.
General Terms (Explain Pixel, Aspect Ratio, PPI & DPI)
Since screen resolution is an important factor in deciding display potential there are some additional terminologies that you must familiarise yourself with.
1. Pixel – pixel is a common word you must have heard which is used as a unit to represent the screen resolution of any display. A pixel represents the illumination of an image. It is a standard unit of programmable colour on the computer screen and is the area where videos or images are composed. Pixel does not have a fixed size and rather depends on the pane size.
2. Aspect ratio – The aspect ratio is a fairly simple term to understand. It is the ratio of an image’s width to its height. Aspect ratio, or AR, is represented by two numbers separated by a colon written as x:y. Technically you can achieve any aspect ratio necessary but the ones commonly used are 16:10, 5:4, 16:9 and 4:3. 16:9 is the most common aspect ratio for monitor screens.
3. PPI – PPI represents pixel per inch and is the measurement of pixel density. It could also represent the monitor’s resolution. A variation of PPI is pixel per centimetre or PPCM.
4. DPI – Dots per inch is a term commonly used in the print media industry. It is the measure of the physical dot density of an image or device output. It differs from PPI which is pixel density from the input perspective, while DPI is from the output perspective.
Whenever you hear talk of a display being HD you can assume that the screen has a minimum resolution of 720p. It was the first time we were able to view images in true high definition. It has been a fan favourite for many viewing enthusiasts for many years, and still holds a candle to that standard.
Even today many big titles that are launched for Playstation and XBOX consoles are launched in 720p. This resolution is reserved for broadcast HD television while a higher resolution is reserved for Blu-ray and streaming platforms.
720p provides the kind of clarity that has become the bottom-line standard for most users today. It satisfies the basic viewing needs of the public. Many opt for a 720p monitors or television because it is cheap and can run a higher resolution picture without any problem. Even though it has been enhanced 3 times without much improvement and there are higher resolutions available, the popularity of 720p has not diminished and you can still find companies manufacturing 720p displays.
1080p (Full HD)
1080p resolution is where high definition reached its true potential, which is why it is known as Full HD. Considering 720p vs 1080p, full HD can provide more than 5 times better picture quality. This is a great improvement on the previous HD available and is best suited for gaming enthusiasts and people who love hosting movie nights for friends and family.
One reason for its popularity comes from the refresh rate it offers. Refresh rate is the number of times an image is displayed in a second. Before 1080p a display was able to achieve a 60Hz of refresh rate. It is a significantly good number, but running a fast-paced shooter on this screen will cause errors like tearing. 1080p can run on a refresh rate of 144HZ, perfect for gamers looking to have an edge while playing first-person shooters.
Though 1080p is a great resolution, it is still considered outdated compared to the recent advancements made in displays today. Therefore, some PS5 and XBOX1 games may not run at their full potential on 1080p.
1440p (Quad HD)
1440p is known as Quad HD and has become a standard resolution for people looking to buy a 27-inch gaming monitor for their custom-built system. It is called Quad HD as it quadruples the resolution prowess of 720p. Other than the clear and crisp images that this monitor offer, the most attractive feature of 1440p monitors is that they can reach the desired refresh rate at which high-performance games can run without any errors.
Before leaping 1440p, make sure you observe how your GPU performs on your current monitor. If, while running your games on a monitor with 1080 resolution you notice tearing and other such errors then a leap tp 1440p is advisable.
4K or 2160p (Ultra HD)
4K Ultra HD is one of the greatest achievement in screen resolution. 4K represents a screen resolution of 3840×2160 pixels. As mentioned earlier, it took the name 4K because four images of 720p can fit into one image of 4K. 4K is one of the greatest development in HD display technology and preferred by many as it is more consumer-friendly and comes at a cheaper price than 8K.
If you are an average gamer or movie enthusiast then you would love the cinematic picture quality that 4K provides. To achieve a good refresh rate you require a display that can match the processing power of your GPU. unfortunately, the previous models did not have that capacity. 4K has the necessary configurations to handle powerful processing that is provided by most third-party graphic cards.
8K or 4320p (Full Ultra HD)
To be honest we were all happy with the viewing experience we are getting from 4K Ultra HD. But since humans are never satisfied we were able to push further and develop better technology in the form of 8K Full Ultra HD. Just like 4K, 8K has a resolution of 7680×4320 and is known as 8K as eight images of 720p resolution can fit in one image of 8K.
8K Full Ultra HD monitors are coveted by many gamers as it is the best resolution possible to attain in today’s time. The one overlooked fact, however, is the amount of processing power necessary to run a game at its full capacity on such a display. Even the recently launched NVIDIA RTX 30 series graphics card struggles to run high-performance games on 8K resolution. While NVIDIA’s DLSS helps accommodate with providing the processing power for the pixel requirement, it doesn’t match it all the way.
720p vs 1080p vs 1440p vs 4K vs 8K – Comparison
Having understood the specifications and functionality of each of the above-mentioned resolutions we shall now compare some of their key features.
1. Pixel Density
As already discussed earlier, pixel density is measured in PPI (pixel per inch) which signifies the number of pixels that are present in an inch. Another way to measure pixel density is PPCM (pixel per centimetre). For better clarity and detailed images, you want a display with the highest pixel density.
There is a simple formula that can be used to identify the PPI for each resolution. The formula depends on horizontal pixels, vertical pixels and diagonal screen size. If we take a 27-inch screen to be our standard, then you get the following pixel densities.
- 720p ~ 54.39 PPI
- 1080p ~ 81.59 PPI
- 1440p ~ 108.79 PPI
- 2160p ~ 163.68 PPI
- 4320p ~ 326.36 PPI
You can see in the case of 720p vs 1080p there is double the difference in pixel density than 1080p vs 1440p. As you keep climbing the resolution chart the difference between adjacent resolutions remains quite consistent till you reach Ultra HD. There is a massive jump between 4K vs 8K where you go from 163.88 PPI to 326.33 PPI.
2. Refresh Rate
Refresh rate is the measure of the number of times a new image can be shown within a second on a display screen. A higher refresh rate means your display unit can project the latest image faster. Today, most units can provide a refresh rate of 60Hz and higher models can boost it up to 165Hz.
When compare 720p vs 1080p you will notice a major difference. While 720p can provide a refresh rate of 60Hz, 1080p can provide about a refresh rate of 144Hz. As you go higher and reach 1440p or higher you will notice the base refresh rate drops to 120Hz. This is common with 2160p and 4320p. This is done because not all units have the capability to match a high refresh rate which may blur the image too much. However, if your GPU can match a higher refresh rate then 4K and 8K monitors can get to 144Hz or even reach 165Hz.
3. Response time
Response time for monitors is the time taken to shift from one colour to another. This is generally measures by shifting the screen from black to white and black again. On average most monitors are be to provide a response time of 10ms.
For your monitor to work at its best potential then your response time depends on your refresh rate. For example, for a 60Hz monitor your response time needs to below 16.67ms, for 144Hz it should be below 6.94ms and for 240Hz it should be below 4.16ms.
Therefore, while 720p can function properly up to 16.67ms without showing signs of ghosting, other resolutions require a GPU with a minimum response time below 7ms.
4. Everyday Use
Choosing a monitor for daily use depends on what you consider daily need. It always makes sense to go for the highest resolution possible, but sometimes the lower HD and full-HD will be efficient enough.
If you planning to buy a television then a 1080p and 1440p resolution should provide the best performance for your viewing pleasure. As an office desktop or for novice gamers, 720p and 1080p monitors will get the job done. For professionals involved with designing and art, a higher resolution of 4K and 8K would be a better choice.
When talking under the umbrella of gaming there are a few factors that you need to consider. The first thing to consider is your gaming preference. If you play simple open-world games like GTA or Assasin’s creed, then you don’t need to push anything higher than a 720p monitor with a refresh rate of 60Hz. If you are into shooter games like Battlefield or Call of Duty you will require a monitor with 144Hz which is possible with a screen resolution of 1080p and higher.
Next, to get the best performance out of the monitor, your graphics card should be able to support it. There is no point in purchasing a display unit with 1440p resolution with a refresh rate of 144Hz if your graphics card cannot match it. If you are purchasing a monitor of 1440p and higher resolution then you need a dedicated third-party graphics card like NVIDIA or AMD
All the above-mentioned resolutions are already in the High Definition spectrum and provide great picture quality. However, each resolution is best suited for specific tasks which may vary based on the users need and system performance. Using the above guide you will have a better understanding of which resolution is best suited for you.