FullCalculator

DPI Calculator

From Width

From Diagonal

Formula

DPI = diagonal pixels / diagonal inches. Diagonal pixels = sqrt(width² + height²). Dot pitch (mm) = 25.4 / DPI.

Frequently Asked Questions

What is the difference between DPI and PPI?
DPI (dots per inch) originally refers to printer resolution, while PPI (pixels per inch) refers to screen resolution. They are often used interchangeably for screens.
What is a good DPI for a monitor?
Standard monitors are around 96 PPI. Retina/HiDPI displays are 200+ PPI. Higher PPI means sharper text and images.

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