
How do you calculate DPI for a mobile phone?
If you know the resolution and screen size, how do you calculate DPI on a mobile phone screen? I hate maths :-P
matt101101 / MOD Jan. 8, 2012 at 20:37
I think you mean PPI? As for the maths, Google it. I bet it'll take less than 30 seconds to find the equation you want.
matt101101 / MOD Jan. 8, 2012 at 20:39
I did it for you:
Theoretically, PPI can be calculated from knowing the diagonal size of the screen in inches and the resolution in pixels (width and height). This can be done in two steps:
1. Calculate diagonal resolution in pixels using the Pythagorean theorem:
2. Calculate PPI:
blizzard7 Jan. 8, 2012 at 21:30
Or you can be lazy like I am:
http://members.ping.de/~sven/dpi.html
CTPAHHIK Jan. 9, 2012 at 12:08
I prefer to be lazy.
matt101101 / MOD Jan. 9, 2012 at 12:43
As do I...
The maths is just copied and pasted from Wikipedia .
Most Useful Answer matt101101 Jan. 8, 2012 at 20:39
I did it for you:


Theoretically, PPI can be calculated from knowing the diagonal size of the screen in inches and the resolution in pixels (width and height). This can be done in two steps:
1. Calculate diagonal resolution in pixels using the Pythagorean theorem:
2. Calculate PPI: