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How to Calculate Pixel Density (PPI)
Formula
PPI measures how tightly pixels are packed on a display. Higher PPI means sharper images.
The formula divides the diagonal pixel count by the physical diagonal size in inches.
Common use cases:
- Comparing display sharpness across devices
- Determining Retina-quality thresholds
- Print resolution planning
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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