Dev & Web

Screen Resolution & DPI Calculator

Enter your screen resolution and physical size to calculate pixels per inch (PPI). See how your display compares to common screens like iPhone, MacBook, and 4K monitors.

Screen width (px)
Screen height (px)
Screen size (inches)
Measure screen diagonally corner to corner (not including bezel)
92 PPI
Low (SD)
1920 × 1080 px
Diagonal: 2,203 px
Reference screens
DeviceResolutionSizePPI
iPhone 15 Pro2556×11796.12″460
iPhone 142532×11706.1″460
MacBook Pro 14"3024×196414.2″254
MacBook Pro 16"3456×223416.2″254
iPad Pro 12.9"2732×204812.9″264
4K Monitor 27"3840×216027″163
Full HD 24"1920×108024″92
Full HD 27"1920×108027″82
Samsung Galaxy S232340×10806.1″425

How it works

The calculator computes the diagonal pixel count using the Pythagorean theorem, then divides by your screen's physical diagonal size to get pixels per inch. Compare your result to the reference table of popular devices.

Frequently asked questions

What is PPI (pixels per inch)?

PPI measures how many pixels fit into one inch of a display. Higher PPI means sharper images. A display above 300 PPI is generally considered Retina quality at typical viewing distances.

What is the difference between PPI and DPI?

PPI refers to screen pixel density, while DPI (dots per inch) refers to printer or image resolution. They measure the same concept (density) in different contexts.

What PPI do I need for a retina display?

Apple's Retina standard is roughly 220+ PPI for laptops and 300+ PPI for phones (viewed at typical distances). At typical desktop distance, 110+ PPI appears sharp.

Does higher PPI always look better?

At very close viewing distances (phones, tablets), higher PPI is clearly better. At typical desktop monitor distances (50-80cm), the difference above 100 PPI is minimal for most users.

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