Technology & Computing
Monitor Pixel Density (PPI) & Retina Viewing Distance Calculator
Calculate a display's pixels-per-inch and the minimum viewing distance at which individual pixels become imperceptible.
Your inputs
Change any value to update the result instantly.
Pixel density
163.1783 PPI
Retina viewing distance
21.0674 in
Retina viewing distance
1.7556 ft
Diagonal resolution
4,405.8143 px
"Retina" distance is where the human eye (20/20 vision) can no longer resolve individual pixels (~1 arcminute per pixel).
Formula and working
PPI = √(width px² + height px²) ÷ diagonal size (in); Retina distance ≈ 1 ÷ (2 × tan(0.5 × 1/60°)) ÷ PPI
- 1
Collect the inputs
Horizontal resolution (px) = 3,840; Vertical resolution (px) = 2,160; Screen diagonal (inches) = 27
- 2
Apply the formula
PPI = √(width px² + height px²) ÷ diagonal size (in); Retina distance ≈ 1 ÷ (2 × tan(0.5 × 1/60°)) ÷ PPI
- 3
Result
Pixel density = 163.1783 PPI
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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