Pixel Density Calculator
Calculate PPI, DPI, pixel pitch, and physical screen dimensions from resolution and diagonal size.
Width: 20.74 in (52.7 cm)
Height: 11.67 in (29.6 cm)
Total Pixels: 2.07 Megapixels
Distance: 3.1 ft (0.94 m)
At this distance or further, a person with 20/20 vision cannot distinguish individual pixels.
A pixel pitch of 0.274 mm means there are 36 pixels packed into every centimetre of the screen.
How pixel density (PPI) is calculated
PPI (pixels per inch) is calculated from the screen resolution and physical size: PPI = √(width² + height²) / diagonal. A higher PPI means more pixels packed into each inch, resulting in sharper text and images. Apple's "Retina" displays are typically 220+ PPI for Macs and 400+ PPI for iPhones.
PPI measures the physical pixel density; "logical DPI" used in CSS is usually 96 dpi on most operating systems. For CSS pixel sizing, try the px to rem converter.
Private & free — this tool runs entirely in your browser.