PPI calculator
Pixel density is the resolution divided by the physical size. Enter a screen size and resolution to get pixels per inch, exact dimensions and a Mac sharpness verdict.
- Physical size
- 23.53″ × 13.24″59.8 × 33.6 cm
- Aspect ratio
- 16:916:9 exact
- Pixel pitch
- 0.1557 mm
- Total pixels
- 8.29 MP
- Pixels vanish beyond
- 21″53.5 cm at 20/20 vision
- Comfortable distance
- 34″86.5 cm
It is too dense for 1× and not dense enough for a comfortable 2×. Scaled to look like 2560 × 1440, text is softer than on a Retina display; at 2×, the UI looks oversized on a 24″-wide screen.
The PPI formula
PPI = √(width² + height²) ÷ diagonal. The top half is the number of pixels along the diagonal, found with Pythagoras. Dividing by the diagonal in inches gives pixels per inch. Example: a 27″ 3840 × 2160 monitor has √(3840² + 2160²) = 4,405.7 pixels on its diagonal, so 4,405.7 ÷ 27 = 163.2 PPI.
What PPI should you aim for?
Higher density means smoother text, but only if the operating system scales the interface so it isn’t tiny. Windows handles any scale factor well, so 140–170 PPI at 150% scaling looks excellent. macOS works best at exactly 1× or 2×, which makes about 110 and 220 PPI the sweet spots.
PPI of popular screens
| Display | Resolution | PPI | Width × height | Mac verdict |
|---|---|---|---|---|
| MacBook Pro 16″ | 3456 × 2234 | 254.0 | 13.6″ × 8.8″ | Retina sharp |
| MacBook Pro 14″ | 3024 × 1964 | 253.9 | 11.9″ × 7.7″ | Retina sharp |
| MacBook Air 13″ | 2560 × 1664 | 224.5 | 11.4″ × 7.4″ | Retina sharp |
| MacBook Air 15″ | 2880 × 1864 | 224.2 | 12.8″ × 8.3″ | Retina sharp |
| 32″ 6K | 6144 × 3456 | 223.8 | 27.5″ × 15.4″ | Retina sharp |
| 27″ 5K | 5120 × 2880 | 217.6 | 23.5″ × 13.2″ | Retina sharp |
| 32″ Pro Display 6K | 6016 × 3384 | 215.7 | 27.9″ × 15.7″ | Retina sharp |
| 21.5″ 4K | 3840 × 2160 | 204.9 | 18.7″ × 10.5″ | Retina sharp |
| 24″ 4K | 3840 × 2160 | 185.1 | 20.7″ × 11.7″ | Retina sharp |
| 34″ ultrawide 5K2K | 5120 × 2160 | 163.4 | 31.3″ × 13.2″ | Scaling compromise |
| 27″ 4K | 3840 × 2160 | 163.2 | 23.5″ × 13.2″ | Scaling compromise |
| 28″ 4K | 3840 × 2160 | 157.4 | 24.4″ × 13.7″ | Scaling compromise |
| 57″ dual 4K ultrawide | 7680 × 2160 | 140.0 | 54.9″ × 15.4″ | Scaled, mostly fine |
| 32″ 4K | 3840 × 2160 | 139.9 | 27.5″ × 15.4″ | Scaled, mostly fine |
| 40″ ultrawide 5K2K | 5120 × 2160 | 138.9 | 36.9″ × 15.5″ | Scaled, mostly fine |
| 24″ 1440p | 2560 × 1440 | 123.4 | 20.7″ × 11.7″ | Sharp, not Retina |
| 34″ ultrawide 1440p | 3440 × 1440 | 109.7 | 31.4″ × 13.1″ | Sharp, not Retina |
| 38″ ultrawide | 3840 × 1600 | 109.5 | 35.1″ × 14.6″ | Sharp, not Retina |
| 27″ 1440p | 2560 × 1440 | 108.8 | 23.5″ × 13.2″ | Sharp, not Retina |
| 49″ super ultrawide | 5120 × 1440 | 108.5 | 47.2″ × 13.3″ | Sharp, not Retina |
| 42″ 4K OLED | 3840 × 2160 | 104.9 | 36.6″ × 20.6″ | Sharp, not Retina |
| 21.5″ 1080p | 1920 × 1080 | 102.5 | 18.7″ × 10.5″ | Sharp, not Retina |
| 39″ ultrawide OLED | 3440 × 1440 | 95.6 | 36.0″ × 15.1″ | Sharp, not Retina |
| 24″ 1920×1200 | 1920 × 1200 | 94.3 | 20.4″ × 12.7″ | Visible pixels |
| 32″ 1440p | 2560 × 1440 | 93.2 | 27.5″ × 15.4″ | Visible pixels |
| 24″ 1080p | 1920 × 1080 | 92.6 | 20.7″ × 11.7″ | Visible pixels |
| 48″ 4K OLED | 3840 × 2160 | 91.8 | 41.8″ × 23.5″ | Visible pixels |
| 45″ ultrawide | 3440 × 1440 | 82.9 | 41.5″ × 17.4″ | Visible pixels |
| 34″ ultrawide 1080p | 2560 × 1080 | 81.7 | 31.3″ × 13.2″ | Visible pixels |
| 27″ 1080p | 1920 × 1080 | 81.6 | 23.5″ × 13.2″ | Visible pixels |
| 55″ 4K TV | 3840 × 2160 | 80.1 | 47.9″ × 27.0″ | Visible pixels |
Calculated from panel diagonal and resolution. “32″” monitors are usually 31.5″ viewable.
Frequently asked questions
How do you calculate PPI?
Divide the diagonal resolution in pixels by the diagonal size in inches: PPI = √(width² + height²) ÷ diagonal. For a 27″ 2560 × 1440 monitor, that is √(2560² + 1440²) ÷ 27 ≈ 108.8 PPI.
How do I find my monitor’s PPI?
Find the native resolution in your display settings (Windows: Settings › System › Display; Mac: System Settings › Displays) and the diagonal size on the model’s spec sheet. Enter both above. Use the viewable size, such as 31.5″ for most “32 inch” monitors.
What is a good PPI for a monitor?
About 90–110 PPI is comfortable at 100% scaling. About 140–165 PPI looks noticeably sharper on Windows with 150% scaling. On a Mac, about 220 PPI gives perfectly sharp 2× rendering at a normal UI size.
What is the PPI of a 27 inch 4K monitor?
A 27″ 3840 × 2160 monitor has 163.2 PPI. For comparison, a 27″ 1440p has 108.8 PPI and a 27″ 5K has 217.6 PPI.
What is the PPI of a 32 inch 4K monitor?
Most “32 inch” 4K monitors are 31.5″ viewable, which gives 139.9 PPI. A true 32.0″ 4K panel has 137.7 PPI.
Is a higher PPI always better?
Only up to a point. Beyond the distance where your eye can resolve single pixels (about 21″ for a 27″ 4K), extra density adds little. Higher resolutions also need UI scaling to keep text readable and a stronger GPU for games.
Is PPI the same as DPI?
Not quite. PPI describes pixels on a screen; DPI describes ink dots from a printer or a mouse sensor’s resolution. People often say DPI for screens, but PPI is the correct term.
What PPI is Retina?
Apple calls a display Retina when its pixels are not visible at a typical viewing distance. For desktop displays that is roughly 220 PPI; for phones, held closer, it is 300–460 PPI.