Diffinity vs KDiff3

Diffinity is a free Windows utility for comparing and merging text files and folders. It shows line-level differences, highlights changed characters or words, and marks added, removed, and changed lines. A thumbnail view summarizes differences, while search can highlight every instance of a selected word. The maker emphasizes readable source-code comparisons, including improved diffing for C-style code and XML. Editing tools include syntax highlighting, customizable tabs, manual alignment markers, and inline differences that update while typing. Diffinity supports Unicode, detects encoding automatically, and warns when compared files use different encodings. It integrates with Windows Explorer, can run from an external device, and accepts file or folder paths with command-line options, including a folder-diff view. Documentation covers configuration with Git and Perforce Helix P4V. The license allows free personal and commercial use and redistribution of unmodified copies, while prohibiting modification and reverse engineering. Listed release 0.9.6, dated 2026-09-16, requires .NET 8.0.

KDiff3 is a free, open-source desktop app for comparing and merging files and folders on Linux, macOS, and Windows. It can compare two or three text files or folders, showing differences line by line and character by character. For merge work, it can combine changes automatically and includes an editor for resolving conflicts, including three-way merges. Folder comparison and Git integration are supported. KDiff3 handles Unicode, UTF-8, and other file encodings; users can highlight or hide whitespace and comment changes, and print differences. It also supports version-control keyword and history merging, with network transparency through KIO. Its listed license is GPL-2.0-or-later. The Free plan costs nothing, and there is no free trial. Linux installation options include Discover or another AppStream store, a distribution package manager, or Flathub. The app page links to a handbook, forum, and bug-reporting page. KDE describes itself as an international community building and distributing free, open-source software since 1996.