Open Source C++ Diff Tools

WinMerge is a Windows tool for visual difference display and merging, for both files and directories. It is highly useful for determining what has changed between file versions, and then merging those changes. WinMerge has Unicode support, Flexible syntax coloring editor, Visual SourceSafe integration, and Windows Shell integration. Regexp filtering for filenames and lines. Side-by-side line difference and highlights differences inside lines. A file map shows the overall file differences in a location pane. The user interface is translated into several languages.

Monitors a number of web pages and tracks changes based on the content of the web pages. Allows to monitor several protocols, including HTTP and HTTPS. Allows to view and record differences. Available for Win7/10/11/+, Linux and others.

WinMergeX is a branch of the WinMerge visual diff tool. It is a MS-Windows diff tool allowing merge of individual files.

Simple, open source crosshair application called AdrixCH (AdrixCH). Customizable by settings window, which can be opened with F12.

XinDiff is a diff utility implementing WinDiff like GUI by an improved LCS algorithm. The key feature in addition to WinDiff is in-place comments for code review.