How many pixels in an inch?

How many pixels in an inch?

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The pixels density, or PPI, of a display is the number of pixels it has per inch. It is a measurement of how many pixels would be present in one inch of your display, whether they are horizontal or vertical. Now that you are aware of your display’s PPI, what good does it do? You’re done if you were merely curious! However, as we mentioned in the opening, a gadget or display PPI is typically just the first of two phases that lead to something far more useful.

Pixels per Inch Has No Single Solution

The number of pixels in an inch would be known if all pixels were the same size, just like how many centimeters there are in an inch (2.54), or how many inches there are in a foot (12). The answer is 58.74 pixels per inch on a 75-inch 4K television, for example, but 440.58 pixels per inch on a 5″-inch full HD smartphone screen since pixels vary in size on different displays. To put it another way, the size and resolution of the screen you’re referring to determine how many pixels per inch, therefore we’ll need to do some math to find the figure you need for yours.

The number of pixels in an inch would be known if all pixels were the same size, just like how many centimeters there are in an inch (2.54), or how many inches there are in a foot (12)
The number of pixels in an inch would be known if all pixels were the same size, just like how many centimeters there are in an inch (2.54), or how many inches there are in a foot (12)

How to Work Out How Many Pixels Are in One Inch

We’ve already done the legwork for you for a number of displays in the Pixels Per Inch Table at the bottom of the page, so don’t worry about that before we get into what appears to be complex math (it isn’t, don’t worry).

If you know the PPI of your display, proceed to How to Use Your Pixels per Inch Number; if not, we’ll calculate it right now using a few straightforward mathematical procedures.

In any event, you’ll need to know the diagonal display size in inches as well as the screen resolution. On your display or device’s technical specifications page, you can find both of these numbers. If you need assistance tracking this down, visit our post on where to get manufacturer tech support details.

If you’re a math whiz, you can skip to the step-by-step instructions after reading the whole equation below:

ppi = (√(w²+h²))/d

where d is the diagonal size of the screen in inches, w is the width resolution in pixels, h is the height resolution in pixels, and ppi is the desired pixels per inch.

Here’s how to do this using a 60″ 4K (3840×2160) screen as an example in case you slept through the order of operations chapter in math class:

  • 38402 Equals 14,745,600 when the width pixels are squared.
  • 21602 Equals 4,665,600 when the height pixels are squared.
  • The sum of those figures is: 14,745,600 + 4,665,600 = 19,411,200
  • Take that number’s square root: √(19,411,200) = 4,405.814
  • Multiplying that result by the screen’s diagonal length yields: 4,405,814 / 60 = 73.43

We calculated the pixels per inch on a 60″ 4K display to be 73.43 PPI in just five easy steps. Now all you have to do is repeat those five procedures using your display and the resolution and size of your screen.

Now that you are aware of your display’s PPI, what good does it do? You’re done if you were merely curious! However, as we mentioned in the opening, a gadget or display PPI is typically just the first of two phases that lead to something far more useful.

If you know the PPI of your display, proceed to How to Use Your Pixels per Inch Number; if not, we'll calculate it right now using a few straightforward mathematical procedures
If you know the PPI of your display, proceed to How to Use Your Pixels per Inch Number; if not, we’ll calculate it right now using a few straightforward mathematical procedures

Calculate the Size of an Image for Use on Another Device

It’s time to put your knowledge about your screen or gadget PPI to good use. Even though you’ll be exhibiting an image on an 84-inch 4K UHD display (52.45 PPI) in the office next week, you may produce or edit it on your 17-inch laptop’s HD screen (129.584 PPI). How can you be certain that the image is being made in a size or with the appropriate level of detail?

You must first be aware of the device’s or display’s PPI in order to respond to this query. You can find one or both of the numbers in the table below, which is where we learned how to accomplish it in the previous part. Additionally, you must be aware of the image’s horizontal and vertical pixel size. It need to be simple to locate in your graphics application since you’re the one who created or edited that.

The directions are below, but if you’re motivated, here are the whole equations:

hsize = w/ppi
vsize = h/ppi

…where w is the image’s width in pixels, h is its height in pixels, and ppi is the PPI of the other display, and hsize and vsize are the image’s horizontal and vertical sizes in inches, respectively, on the other display.

If your image is 950×375 pixels in size and you want to display it on an 84-inch 4K (3840×2160) screen (52.45 PPI), follow these steps:

  • 950 / 52.45 = 18.11 inches when the width is divided by the PPI.
  • 375 / 52.45 = 7.15 inches when the height is divided by the PPI.

Here, we demonstrated that an image of 950×375 pixels will appear to be 18.11″ by 7.15″ on an 84-inch 4K TV, regardless of how “large” or “little” it may appear to be on your screen.

Now that you know that information, you may use it however you see fit. Perhaps that is exactly what you were looking for, or perhaps that is not large enough given that an 84-inch screen is around 73 inches wide and 41 inches tall!

How can you be certain that the image is being made in a size or with the appropriate level of detail?
How can you be certain that the image is being made in a size or with the appropriate level of detail?

Identify the Image Size That Will Print in Full Resolution

To determine how big an image will be on paper, you don’t need to calculate your device’s or display’s PPI.

There are only three pieces of information you need to be aware of: the horizontal and vertical pixel dimensions and the PPI of the image. The image’s characteristics, which you may locate in your graphics editing tool, contain all three bits of information.

The formulas are as follows:

hsize = w/ppi vsize = h/ppi

…where w is the image’s width in pixels, h is its height in pixels, and ppi is the image’s PPI. These values represent the image’s horizontal and vertical print sizes in inches, respectively.

If your image is 375×148 pixels in size and has a 72 PPI, follow these steps to achieve it:

  • PPI = 375 / 72 = 5.21 inches when the width is divided by PPI.
  • PPI = 148 / 72 = 2.06 inches when height is divided by PPI.

The image will be printed at a physical size of 5.21 by 2.06 inches, assuming that you don’t scale it while printing. Make the calculations using an existing image, then print them out – it always works!

No matter what DPI setting your printer has—300, 600, 1200, etc.—the image will print at the same size. This figure, which closely resembles PPI and indicates the “quality” with which the image given to the printer is printed, shouldn’t be taken into account when determining the appropriate image size.

To determine how big an image will be on paper, you don't need to calculate your device's or display's PPI
To determine how big an image will be on paper, you don’t need to calculate your device’s or display’s PPI
PPI Cheat Sheet
Size (in) 8K UHD (7680×4320) 4K UHD (3840×2160) Full HD (1920×1080)
145 60.770 30.385 15.192
110 80.106 40.053 20.026
85 103.666 51.833 25.917
84 104.900 52.450 26.225
80 110.145 55.073 27.536
75 117.488 58.744 29.372
70 125.880 62.940 31.470
65 135.564 67.782 33.891
64.5 136.614 68.307 34.154
60 146.860 73.430 36.715
58 151.925 75.962 37.981
56.2 156.791 78.395 39.198
55 160.211 80.106 40.053
50 176.233 88.116 44.058
46 191.557 95.779 47.889
43 204.922 102.461 51.230
42 209.801 104.900 52.450
40 220.291 110.145 55.073
39 225.939 112.970 56.485
37 238.152 119.076 59.538
32 275.363 137.682 68.841
31.5 279.734 139.867 69.934
30 293.721 146.860 73.430
27.8 316.965 158.483 79.241
27 326.357 163.178 81.589
24 367.151 183.576 91.788
23 383.114 191.557 95.779
21.5 409.843 204.922 102.461
17.3 509.343 254.671 127.336
15.4 572.184 286.092 143.046
13.3 662.528 331.264 165.632
11.6 759.623 379.812 189.906
10.6 831.286 415.643 207.821
9.6 917.878 458.939 229.469
5 1762.326 881.163 440.581
4.8 1835.756 917.878 458.939
4.7 1874.815 937.407 468.704
4.5 1958.140 979.070 489.535
The image will be printed at a physical size of 5.21 by 2.06 inches, assuming that you don't scale it while printing
The image will be printed at a physical size of 5.21 by 2.06 inches, assuming that you don’t scale it while printing

Naturally, not every gadget or screen is exactly 8K UHD, 4K UHD, or Full HD (1080p). Here is another table that lists several well-known gadgets with unusual resolutions along with their determined PPI:

PPIs for Popular Devices
Device Size (in) Resolution (x/y) PPI
Dell Venue 11 Pro 10.8 1920×1080 203.972
Essential Phone 5.71 2560×1312 503.786
Google Pixel 5a 6.34 1080×2400 415.111
Google Pixel 6 6.4 1080×2400 411.220
Google Pixel 6 Pro 6.7 1440×3120 512.877
Google Pixelbook Go 13.3 3840×2160 331.264
HTC U12+ 6.0 1440×2880 536.656
HTC Wildfire E3 6.52 720×1560 263.518
iMac 4.5K 23.5 4480×2520 218.728
iMac 5K 27 5120×2880 217.571
iPad Mini Retina 8.3 2266×1488 326.613
iPad Air 10.9 2360×1640 263.659
iPad Pro 12.9 2732×2048 264.682
iPhone 11 6.1 1792×828 323.614
iPhone 13/12 Pro & 13/12 6.1 2532×1170 457.254
iPhone 13 Pro Max 6.7 2778×1284 456.773
LG G8X ThinQ 6.4 1080×2340 402.689
LG Velvet 6.8 1080×2460 395.093
MacBook 12 12 2304×1440 226.416
MacBook Air 11 11.6 1366×768 135.094
MacBook Air 13 13.3 1440×900 127.678
MacBook Pro (2020) 13.3 2560×1600 226.983
MacBook Pro (2021) 16.2 3456×2234 254.023
Nexus 10 10.1 2560×1600 298.898
Nexus 6 6 1440×2560 489.535
Nexus 6P 5.7 1440×2560 515.300
Nexus 9 8.9 2048×1536 287.640
OnePlus 9 Pro 6.7 3216×1440 525.921
OnePlus Nord N200 6.49 1080×2400 405.517
Samsung Galaxy Note 20 Ultra 6.9 3088×1440 493.804
Samsung Galaxy S21+ 6.7 1080×2400 392.807
Samsung Galaxy Tab S7+ 12.4 1752×2800 266.367
Samsung Galaxy Z Flip 3 6.7 2640×1080 425.726
Samsung Galaxy Z Fold 3 7.6 2208×1768 372.187
Sony Xperia 5 III 6.1 1080×2520 449.455
Surface Book 3 15 3240×2160 259.600
Surface Go 3 10.5 1920×1280 219.767
Surface Laptop Studio 14.4 2400×1600 200.308
Surface Pro 8 13 2880×1920 266.256

Some Frequently Asked Questions

How do I translate pixels into inches?

Divide the total number of pixels by the PPI (pixels per inch) parameter of the display. For instance, 200 pixels on a screen with 81 PPI would be 200 / 81 = 2.5 inches.

At 300 dpi, how many pixels are there per inch?

Dots per inch (DPI) and pixels per inch (PPI), which are interchangeable but applied to various devices, are the same measurement. In printers, where dots are used to create the text and graphics, DPI is used. Screens (monitors, phones, etc.) that use pixels to create images use PPI.

In printers, where dots are used to create the text and graphics, DPI is used. Screens (monitors, phones, etc.) that use pixels to create images use PPI
In printers, where dots are used to create the text and graphics, DPI is used. Screens (monitors, phones, etc.) that use pixels to create images use PPI

How many pixels are there in a single inch?

The PPI (pixels per inch) of the screen in question determines the answer. A 27-inch 1080p monitor, for instance, contains 81 pixels per inch of the screen. The screen is 13.2 inches high, according to measurements. Thus, 1080 / 13.2 is 81 PPI (rounding down to the nearest pixel).

On an iPhone 13, how many pixels make up an inch?

In 460 pixels. The 6.1-inch (diagonal) screen of the iPhone 13 has a resolution of 2532 x 1170 pixels and a pixel density of 460. (pixels per inch).

Final Words

If you were unable to locate your resolution or device, don’t panic. No matter the size or quality of your device, you can use the arithmetic we just discussed to determine how many pixels there are in an inch.

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