FileMerge
Being part of its developer toolset, Apple's own merge tool comes at no additional costs. It might not be the most elegant tool, but it's definitely a solid one that does the job of comparing & merging text.
GitX-dev is a fork (variant) of GitX, a long-defunct GUI for the git version-control system. It has been maintained and enhanced with productivity and friendliness oriented changes, with effort focused on making a first-class, maintainable tool for today's active developers.
Beyond Compare
- Fork - Fast and friendly Git client for Mac. Gitbar - Open-source，display Github contribution statistics on your menu bar. GitFinder - Fast and lightweight Git client for Mac with Finder integration. GitHub Desktop - The official GitHub GUI. GitKraken - The most popular Git GUI for Windows, Mac and Linux.
- Choosing the right Git GUI client for Mac OS X Vincent Danen is a Subversion fan, but coming around to Git for the Mac. Before learning the command line for Git, he shopped around for a GUI client.
Originally a product for Microsoft Windows, the Beyond Compare team has contributed a fine diff tool to the Mac platform. Like Araxis Merge and DeltaWalker, it goes beyond (pun intended) comparing simple text and also allows diffing Word and PDF contents. In its 'Pro Version', it also supports merging.
Araxis Merge
One of the few diff tools that works with more than just text and image files, Araxis Merge lets you also compare office documents (like MS Word, Excel, Powerpoint, or ODF). For people working on both Windows and Mac, it's great to know that a single license is valid for both platforms.
NEW: Image Diffing in Tower! Our popular Git client Tower now supports Image Diffing for a variety of formats (including PNG, JPG, GIF, BMP, TIFF, JPEG2000, and HEIC). In both the Working Copy and various History / Changeset views, you can now see the actual images - and how they were changed! Try it yourself - for free!
DeltaWalker
Just like Araxis, the DeltaWalker app also lets you compare office files. However, it goes one step further by letting you compare file archives like ZIP, JAR, and TAR files. Also, if you're regularly performing comparisons on a folder basis, DeltaWalker shines with a great performance in this area.
Kaleidoscope
Originally developed by 'Sofa', Kaleidoscope was later acquired by 'BlackPixel' - who did a great job in making it one of the best diff & merge tools for the Mac. Its beautiful user interface and great image diffing capabilities are what set it apart.
Free Alternatives
In case you're looking for a free alternative to the standard FileMerge app, you should also have a look at P4Merge and DiffMerge.
Both can't compare in terms of features and user interface with their commercial competitors - but make for a valid alternative on Mac, Windows, and Linux.
Integrations
Git Ui For Windows
Another aspect to watch out for is integrations: before choosing your favorite tool, you should make sure that it plays nicely with the rest of your tool chain. I can already confirm that all of the mentioned tools work seamlessly at least with Tower, our own Git client.
If you don't need the power of a dedicated Diff tool application, the integrated diff views in Tower might be absolutely sufficient for you:
In case you don't know Tower: it's the Git desktop client for Mac and Windows that helps thousands of developers and designers to easily & productively work with the Git version control system. Try it 30 days for free!
Conclusion
Diff & merge apps are amongst the most underestimated tools. But a good one can be really helpful in a lot of situations. Try one of the above and see for yourself!
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