If you are looking for a simple, yet powerful graphical tool that helps to merge and comparing text files, Diffuse can be your best bet. It also shows the file pairs that are either similar or different. Furthermore, it compares the two folders side-by-side, while displaying which files are only present in a single file or in the other. It enables the files to merge automatically whenever possible, and also allows complete control on the editing of the file generated. Similarly, it also shows the modifications (merging) between three files, graphically. Also, it features options like intra-line highlighting and complete support for editing. Moreover, it graphically represents the modifications between the two files. The application visually compares files and even merges them on major platforms like Windows, Mac, and Linux.

Those looking for a file comparison tool would find DiffMerge much helpful due to its powerful features. From options to customize keyboard shortcuts, getting file backups, or personalizing the UI fonts and colors to supporting multiple languages, there’s a lot that it’s capable of. It gets downloaded quickly and is pretty easy with no complications involved. It lets you compare two files (text or binary) to check if any of them is a duplicate. Despite being free, it’s an advanced and responsive file comparison tool for Windows.

AptDiff is a freeware that’s now discontinued, but still available to download through some third-party websites.

Windows diff folders