Question 1

How is screen size measured?

Accepted Answer

Screen size is measured diagonally in inches, from one corner of the visible area to the opposite corner. The width and height are smaller than the diagonal — for a 16:9 screen, the diagonal is about 1.794× the height.

Question 2

What is PPI?

Accepted Answer

PPI (Pixels Per Inch) tells you how densely packed the pixels are on the screen. Higher PPI = sharper image. A modern phone is around 400-500 PPI, a typical 4K monitor is around 160 PPI, and a 1080p 27-inch monitor is about 82 PPI.

Question 3

How far should I sit from my TV?

Accepted Answer

For 1080p content, the recommended distance is about 1.5-2.5× the screen diagonal. For 4K content, you can sit closer — around 1-1.5× the diagonal — because the higher pixel density hides individual pixels from your seat.

Question 4

Can I enter a resolution to get PPI?

Accepted Answer

Yes. Enter the screen width and height in cm or inches and the resolution in pixels. The calculator instantly gives you the PPI and a pixel density rating (Retina, HiDPI, standard).