🖥️ Display Optics & Visual Acuity
Screen Resolution, DPI & PPI Calculator
Compute monitor pixel density (Pixels Per Inch), subpixel dot pitch in millimeters, total display megapixels, and the human 20/20 visual acuity Retina distance.
24" 1080p Monitor
27" 1440p QHD Monitor
27" 4K UHD Monitor
MacBook Pro 14" (Liquid Retina)
iPhone 15 (6.1" OLED)
Screen Specs
in (″)
Pixel Density (PPI / DPI)
108.79 PPI
Dot Pitch
0.2335 mm
Total Pixels
3.69 MP
Aspect Ratio
16:9
💡 Visual Acuity (Retina Standard):
At a normal viewing distance beyond 31.6 inches, individual pixels become indistinguishable to a person with standard 20/20 vision (1 arcminute resolving threshold).
Understanding Display PPI & Visual Acuity
Pixel density measures how sharply rendered icons and typography appear on digital displays:
- Formula: $$\text{PPI} = \frac{\sqrt{W^2 + H^2}}{\text{Diagonal Inches}}$$
- Retina Threshold: Derived from standard Snellen 20/20 human eye resolution (1 arcminute = $1/60^\circ$ of visual angle), representing the distance where pixels blend into continuous reality: $$\text{Distance (in)} = \frac{3,438}{\text{PPI}}$$