PPI Calculator
Work out a screen's pixel density in PPI from its resolution and physical size.
How sharp a screen is
Pixels per inch measures how densely a screen packs its pixels, which is what makes a display look sharp or coarse. This works out the PPI from a screen's resolution and its diagonal size, so you can compare how crisp two displays actually are rather than trusting resolution alone.
Enter the resolution and screen size to get the PPI.
Resolution alone is misleading
The reason PPI matters is that the same resolution looks very different at different sizes — a 1080p phone is far sharper than a 1080p television, because the same pixels are squeezed into a much smaller screen. So resolution alone does not tell you sharpness; pixel density does. There is also a point beyond which more density is imperceptible at a normal viewing distance, which is why phones, held close, benefit from very high PPI while a TV watched from across the room does not need it.
PPI Calculator FAQ
Why isn't resolution enough to judge sharpness?
Because the same resolution on a bigger screen is less dense — a 1080p phone is far sharper than a 1080p TV, since PPI accounts for size.
Is higher PPI always better?
Up to a point — beyond what the eye can resolve at a normal distance, extra density is imperceptible, which is why TVs need less than phones.
Is anything uploaded?
No. The calculation happens in your browser.