How sharp is a screen, really? Pixel density — pixels per inch, or PPI — is the number that answers it, and it’s the one spec sheets love to bury. Put in a screen’s resolution and its diagonal size and this works it out, along with the total megapixels and how it stacks up against “Retina-class” sharpness. Everything runs in your browser; nothing is sent or stored.
One caveat worth repeating: PPI isn’t the whole story. A phone held 30 cm from your face needs far more density to look sharp than a TV across the room. Perceived sharpness is density combined with viewing distance — which is why a 4K TV and a flagship phone can both look flawless at wildly different PPI.
Comparing handsets? Browse the gadgets & tech posts.