Code Compare is a free compare tool designed to compare and merge differing files and folders. Code Compare integrates with all popular source control systems: TFS, SVN, Git, Mercurial, and Perforce. Code Compare is shipped both as a standalone file diff tool and a Visual Studio extension.
GitKraken - The intuitive, fast, and beautiful cross-platform Git client.
Beyond Compare - Beyond Compare allows you to compare files and folders.
SmartGit - SmartGit is a front-end for the distributed version control system Git and runs on Windows, Mac OS...
WinMerge - WinMerge is an open source differencing and merging tool for Windows.
SourceTree - Mac and Windows client for Mercurial and Git.
Araxis Merge - Home of the award-winning Araxis Merge two and three-way file comparison (diff) and merging application, Araxis Find Duplicate Files, Araxis Replace In Files, and the Araxis Ketura issue tracking, project scheduling and time tracking application.