Surprisingly, could not find quick tool to compare various screen sizes and resolutions.

It is useful to understand why a modern 14 inch display (with 16:9 ratio) is almost a centimeter shorter vertically than older 12 inch (with 4:3 ratio).

 

So here it is:

Diagonal inches or select
Resolution x or select


 Results:

Screen area: square inches.
Width: , height: inches.
Pixel density: pixels per inch.