Get display resolution from the command line for Linux Desktop

Use the command xrandr. Without any argument it displays the available resolutions and the current one (with an asterisk), for instance:

$ xrandr | fgrep '*'

Alternative solution: xdpyinfo | grep dimensions. xdpyinfo is older than xrandr, so might be more portable if you happen to use a very old distribution or some different X server.

You can get the horizontal and vertical resolutions using the following command:

xdpyinfo | grep dimensions | awk '{print $2}' | awk -Fx '{print $1, $2}'

or, in more compact form (as suggested by Peter.O in this comment):

xdpyinfo | awk -F'[ x]+' '/dimensions:/{print $3, $4}' 

For exmaple, on a 1600x900 display this will produce the following output:

1600 900

You can then place the values into separate variables using the command:

read RES_X RES_Y <<<$(xdpyinfo | awk -F'[ x]+' '/dimensions:/{print $3, $4}')

Display the values of the above variables using the command:

echo $RES_X, $RES_Y

On a 1600x900 display, the output is:

1600, 900