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Whenever I run xdpyinfo | grep dots in the Terminal I get:

resolution:    96x96 dots per inch

I have a 14" 2560 x 1440 screen, so I understand the dpi of this screen should be anything around 200 dpi. How does Xorg determines which is the correct dpi for the screen? I am not asking how to change the dpi configuration but how is it defined by Xorg.

marked as duplicate by Andrea Lazzarotto, Eric Carvalho, WinEunuuchs2Unix, Kevin Bowen, karel Nov 25 '16 at 10:34

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • Your screen has a diagonal of 2937.2 pixels. This means your ideal DPI is roughly 210. – Andrea Lazzarotto Nov 24 '16 at 14:26
  • I dont think this is a duplicate. The other questions points to how to change the dpi settings, while my question is related to how xorg determines the dpi and if it is doing it fine. – ig343 Nov 24 '16 at 14:28
  • 2
    “how xorg determines the dpi” Simple, it's hardcoded to 96 no matter what (until you set it up explicitly). It is not "fine", it is just a legacy assumption from when displays were always 96 DPI. Also Windows does a similar thing unless you change it. Setting up the right DPI value should give you a more natural UI size, and also a true "100% scale" in applications like LibreOffice or GIMP. – Andrea Lazzarotto Nov 24 '16 at 14:31
  • I can't understand how in any way this and the other questions could be the same... – ig343 Nov 25 '16 at 13:17

Apparently Xorg might try to determine your screen size but will not always manage to do that correctly. In that case, one should set the correct screen size for that particular monitor so Xorg will know the dpi.


  • You might want to include the essential parts of the information in your answer, as link-only answers are generally not well received here. – Andrea Lazzarotto Nov 24 '16 at 17:04

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