KDiff3Īnother free and open source tool answers to the name of KDiff3. It comes in standard and professional editions, and for people working on both Windows and macOS, it's good to know that a single license is valid for both platforms. It also lets you compare office documents (like MS Word, Excel, Powerpoint, or ODF).
Just like Beyond Compare, Araxis Merge supports more than just text and image files. The 'Pro' version also includes a solid three-way merge. It goes well beyond (pun intended) diffing simple text and also allows comparing PDF, Excel and image files. The Beyond Compare team makes a fine diff tool for Windows (as well as macOS and Linux, by the way). Apart from diffing files, Meld also supports comparison of folders. It supports three-way comparing and merging and lets you edit files directly from the comparison view. Being free and open source, Meld is a very popular tool on Windows (it's also available for Linux).