How it works
PPI (Pixels Per Inch) measures how many pixels are packed into each inch of screen. The same resolution looks sharper on a smaller panel because PPI rises as size shrinks. When shopping for a laptop or monitor, check PPI relative to screen size, not just the raw resolution, to get a realistic sense of sharpness.
FAQ
Q. Is higher PPI always better?
A. Sharpness improves, but it also raises GPU load and can make UI elements appear smaller. Find the level that fits your use case.
Q. What counts as a 'Retina' display?
A. There's no fixed number, but a PPI where individual pixels become invisible at normal viewing distance (roughly 200+) is commonly called Retina-level.