screen physical size, DPI, font size - how does it work?

Ross Burton ross at
Sun Oct 7 08:15:02 PDT 2007

On Sun, 2007-10-07 at 14:37 +0200, Alexej Davidov wrote:
> The other thing is: if I set the resolution to the theoretically
> correct value, which is 125x125 dpi in my case (1400x1025 at
> 285x215mm), all the fonts are far to big. 

The fonts are not too big, they are the correct size.  You are
specifying sizes in points, so by changing the relation between pixels
and inches, the size of the fonts obviously changes.

You can verify this by setting the screen font size to something like
18pt, printing out some text at 18pt, and then compare them.  For
typical setups like a monitor on a desk, set the correct DPI and then
set the font size to the right size.

My laptop's screen is 246x185mm at 1024x786 which works out to 105dpi,
and my preferred widget font size is 7.5pt.

Ross Burton                                 mail: ross at
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