PPI calculator for screen size and aspect ratio

PPI calculator: pixel density from resolution and diagonal, plus screen width and height, aspect ratio, dot pitch and the distance where pixels blend.

ನವೀಕರಿಸಲಾಗಿದೆ ಪರಿಶೀಲಿಸಿದ ಉದಾಹರಣೆಗಳು: 5

ಪ್ರಯತ್ನಿಸಿ
Pixel density
PPI
Pixel density: 108.79 PPI
ದಶಮಾಂಶ ಸ್ಥಾನಗಳು: 2; ಹತ್ತಿರದ ಮೌಲ್ಯಕ್ಕೆ; ಸಮದೂರದಲ್ಲಿದ್ದರೆ ಸಮ ಅಂಕೆಯ ಕಡೆಗೆ
ಆಕಾರ ಅನುಪಾತ
16:9
ಅಗಲ
23.53in / 59.77cm
ಎತ್ತರ
13.24in / 33.62cm
Dot pitch
0.2335mm
Total pixels
3.69MP
Pixels blend beyond
31.6in / 80.3cm

A 27-inch 2,560 × 1,440 screen (16:9) packs 108.8 pixels per inch into a 23.5 × 13.2 in panel; beyond about 32 in (80 cm) a person with 20/20 vision can't pick out single pixels.

Screen outline

27 in diagonal23.53 in · 2,560 px13.24 in · 1,440 px
ಲೆಕ್ಕಾಚಾರದ ವಿಧಾನ S
  1. Diagonal in pixels

    2,5602+1,4402=2,937.21\sqrt{2{,}560^2 + 1{,}440^2} = 2{,}937.21
  2. Pixels per inch

    2,937.2127=108.79\frac{2{,}937.21}{27} = 108.79
  3. Physical width and height

    27×2,5602,937.21=23.53 in,27×1,4402,937.21=13.24 in27 \times \frac{2{,}560}{2{,}937.21} = 23.53\ \text{in},\quad 27 \times \frac{1{,}440}{2{,}937.21} = 13.24\ \text{in}
  4. Dot pitch

    25.4108.79=0.2335 mm\frac{25.4}{108.79} = 0.2335\ \text{mm}
  5. Distance where single pixels blend

    1108.79×tan⁡(1′)=31.6 in\frac{1}{108.79 \times \tan(1')} = 31.6\ \text{in}

    At this distance one pixel spans 1 arcminute, the detail 20/20 vision resolves; this is the idea behind “retina” displays.

PPI calculator for screen size and aspect ratio ಬಗ್ಗೆ

Pixel density is the diagonal resolution in pixels divided by the diagonal size in inches: PPI = √(w² + h²) ÷ diagonal. The same ratio splits the diagonal into the physical width and height, dot pitch is 25.4 mm ÷ PPI, and the blend distance is where one pixel spans 1 arcminute, the detail that 20/20 vision resolves.

The default 27-inch 2560 × 1440 monitor has 108.79 PPI, a 16:9 panel of 23.53 × 13.24 inches, and pixels that blend beyond about 31.6 inches (80 cm). The same size at 4K, 3840 × 2160, reaches 163.18 PPI and blends beyond 21 inches.

Advertised diagonals are rounded, so results can differ slightly from a spec sheet. The blend distance assumes 20/20 vision; people with sharper eyesight can pick out pixels from further away.

ಪರಿಹರಿಸಿದ ಉದಾಹರಣೆಗಳು

27-inch 2560 × 1440 monitor

Diagonal
27 in
Horizontal pixels
2560
Vertical pixels
1440
Pixel density
108.79 PPI
ಆಕಾರ ಅನುಪಾತ
16:9
ಅಗಲ
23.53 in
ಎತ್ತರ
13.24 in
Dot pitch
0.2335 mm
Pixels blend beyond
31.6 in
Total pixels
3.69 MP

ಪರಿಶೀಲನೆಯ ಮೂಲ: Python decimal: √(2560² + 1440²)/27; retina distance 1/(PPI·tan(π/10800))

13.3-inch 2560 × 1600 laptop

Diagonal
13.3 in
Horizontal pixels
2560
Vertical pixels
1600
Pixel density
227.00 PPI
ಆಕಾರ ಅನುಪಾತ
8:5 (16:10)

ಪರಿಶೀಲನೆಯ ಮೂಲ: Apple MacBook Air (M1, 2020) tech specs list 227 ppi; Python decimal gives 226.983

Square screen

Diagonal
10 in
Horizontal pixels
1000
Vertical pixels
1000
Pixel density
141.42 PPI
ಆಕಾರ ಅನುಪಾತ
1:1
ಅಗಲ
7.07 in

ಪರಿಶೀಲನೆಯ ಮೂಲ: Python decimal: 1000√2/10

1366 × 768 is only nearly 16:9

Diagonal
15.6 in
Horizontal pixels
1366
Vertical pixels
768
Pixel density
100.45 PPI
ಆಕಾರ ಅನುಪಾತ
683:384 (≈ 16:9)

ಪರಿಶೀಲನೆಯ ಮೂಲ: Python decimal and math.gcd: gcd(1366, 768) = 2

ಪ್ರಶ್ನೆಗಳು

How do you calculate PPI?

Find the diagonal in pixels with Pythagoras and divide it by the diagonal in inches. A 27-inch 2560 × 1440 monitor has √(2560² + 1440²) = 2,937.2 pixels along the diagonal, so 2,937.2 ÷ 27 = 108.79 PPI. Use the visible screen diagonal, not the outside of the case.

What PPI counts as a Retina display?

Apple introduced the name with the iPhone 4 in 2010: a 960 × 640 screen at 326 pixels per inch, where Apple said the eye cannot make out individual pixels at a normal viewing distance. At 326 PPI one pixel spans 1 arcminute from 10.5 inches, so the threshold depends on distance: a 27-inch 4K monitor at 163 PPI passes the same test from 21 inches.

How far should I sit from a 4K TV?

To stop seeing single pixels with 20/20 vision, sit at least about 43 inches (1.1 m) from a 55-inch 4K TV, which has 80.1 PPI, or 51 inches (1.3 m) from a 65-inch one. Beyond about 86 inches (2.2 m), a 55-inch 1080p screen blends its pixels too, so 4K adds little visible detail from that far away.

What aspect ratio is 2560 × 1440?

16:9: divide both numbers by their greatest common divisor, 160. TVs and most monitors are 16:9, while some laptops use 16:10, such as the 13.3-inch 2560 × 1600 MacBook Air (8:5 when reduced). A resolution such as 1366 × 768 reduces only to 683:384, which is within 0.05% of 16:9.

Why does my result differ from the spec sheet?

Advertised diagonals are rounded. The iPhone 4's 960 × 640 screen is sold as 3.5 inches, which gives 329.7 PPI, while Apple quotes 326 PPI, matching a diagonal of about 3.54 inches. Enter the diagonal to two decimal places when you know it, and check that the resolution is the panel's native one.

“PPI calculator for screen size and aspect ratio” ಎಷ್ಟು ನಿಖರವಾಗಿದೆ?

ನಿಖರತೆ ನಿಮ್ಮ ಇನ್‌ಪುಟ್‌ಗಳು ಮತ್ತು ವಿಧಾನದ ಊಹೆಗಳನ್ನು ಅವಲಂಬಿಸಿದೆ. ದಶಮಾಂಶ ಗಣನೆ 50 ಸಾರ್ಥಕ ಅಂಕೆಗಳನ್ನು ಬಳಸುತ್ತದೆ. ಆದರೆ ಅಂದಾಜುಗಳು, ಸಂಖ್ಯಾತ್ಮಕ ವಿಧಾನಗಳು ಮತ್ತು ಮೂಲ ದತ್ತಾಂಶ ಕಡಿಮೆ ನಿಖರವಾಗಿರಬಹುದು; ಪ್ರದರ್ಶಿತ ಮೌಲ್ಯಗಳನ್ನು ರೌಂಡ್ ಮಾಡುವುದರಿಂದ ಈ ಮಿತಿಗಳು ನಿವಾರಣೆಯಾಗುವುದಿಲ್ಲ. ಸ್ವತಂತ್ರ ಮೂಲಗಳ ಪರಿಹಾರಗಳೊಂದಿಗೆ ಪರಿಶೀಲಿಸಿದ ಉದಾಹರಣೆಗಳು: 5. ಉದಾಹರಣೆಗೆ, “27-inch 2560 × 1440 monitor” ಅನ್ನು Python decimal: √(2560² + 1440²)/27; retina distance 1/(PPI·tan(π/10800)) ಜೊತೆಗೆ ಪರಿಶೀಲಿಸಲಾಗುತ್ತದೆ.

ಈ ವಿಧಾನದ ಮೂಲ ಯಾವುದು?

Pixel density — PPI from resolution and diagonal; Visual acuity — 20/20 vision resolves detail of 1 arcminute.

ಈ ಕ್ಯಾಲ್ಕುಲೇಟರ್ ಬಗ್ಗೆ

PPI=w2+h2diagonal (in)dblend=1PPI⋅tan⁡(1′)\begin{gathered}\text{PPI} = \frac{\sqrt{w^2 + h^2}}{\text{diagonal (in)}} \\ d_{\text{blend}} = \frac{1}{\text{PPI}\cdot\tan(1')}\end{gathered}

ಮೂಲಗಳು

  1. Pixel density — PPI from resolution and diagonal
  2. Visual acuity — 20/20 vision resolves detail of 1 arcminute

ಆಧಾರಗಳೊಂದಿಗೆ ಪರಿಶೀಲಿಸಲಾಗಿದೆ

ಈ ಕ್ಯಾಲ್ಕುಲೇಟರ್‌ನಲ್ಲಿ ಸ್ವತಂತ್ರ ಆಧಾರಗಳಿಂದ ಉತ್ತರಗಳನ್ನು ಪಡೆದ 5 ಬಿಡಿಸಿದ ಉದಾಹರಣೆಗಳಿವೆ. ಇವು ಪರೀಕ್ಷಾ ಸಮೂಹದಲ್ಲಿ ನಡೆಯುತ್ತವೆ; ನೀವು ಇಲ್ಲಿಯೂ ನಡೆಸಬಹುದು.

ಸಂಬಂಧಿತ ಕ್ಯಾಲ್ಕುಲೇಟರ್‌ಗಳು