KDiff3 supports printing for textfile differences. The → menu item (Ctrl+P) opens a dialog that allows you to select the printer and to adjust other options.
There are several possibilities to adjust the range. Due to different printing dialogs on different operating systems, the method to achieve certain range selections varies.
Print a page starting at the first visible line in the window. (On systems without this option this can be achieved by specifying page number 10000 for printing.)
Before choosing to print select text with the mouse (like for copy and paste) in one of the diff input windows to define the start and end line. If no text in one of the diff input windows was selected, then this won't be an available choice. (On systems without this option this can be achived by specifying page number 9999 for printing.)
Specify the first and last page.
Other important options for printing will be taken from the normal options:
Font, font size
Show line numbers
Landscape formatting is also recommended for printing.