I need a Windows tool which can compare 2 files in .txt format and output the difference. It should also work with large files. Example below: Text1.txt Apple Orange Banana Text2.txt Apple Orange Banana Lemon Output.txt Lemon So how could I do this in Windows without using that "grep" tool which is Linux thing? I am also working with large files 100k rows. I tried this but it couldn't load my files properly: http://www.sobolsoft.com/comparetextline Also textmechanic.com doesn't seem to have this kind of tool.