About PPI Calculator
Compute display pixel density (PPI), physical pixel pitch in millimeters, and the human visual acuity threshold distance where pixels disappear.
Key Capabilities & Features
- Calculates exact screen pixel density (PPI) from display resolution and diagonal size
- Computes physical subpixel dot pitch in millimeters
- Apple Retina display viewing distance threshold based on 20/20 human visual acuity
- Popular device presets: iPhone, MacBook Pro, 4K monitors, and desktop displays
How to Use PPI Calculator
1
Enter Screen Resolution
Input your display width and height in pixels.
2
Enter Diagonal Inches
Input your screen diagonal size (e.g. 27 inches or 6.1 inches).
3
View Retina Distance
See the exact distance where individual pixels become invisible.
Privacy & In-Browser Execution Guarantee
100% client-side calculation. Your data stays private in your browser.
Frequently Asked Questions
What is the difference between DPI and PPI?
PPI (Pixels Per Inch) measures electronic digital screens and camera sensors. DPI (Dots Per Inch) measures physical ink droplets deposited by a printer onto paper.
What makes a display Retina?
A display is Retina when viewed at a distance where its pixel density exceeds human visual resolution (1 arcminute of acuity, or 3,438 / PPI inches).