Spot the differences. Merge in seconds.

With text merge, three-way merge, folder comparison, and the ability to ignore whitespace-only differences, Kaleidoscope integrates perfectly with the version-control systems you already use.


Easy Workflow Integration

- Subversion, Git, Mercurial, Bazaar, and Perforce support
- Works as a fully functional diff or merge tool
- Supported by a growing list of GUI source control management apps
- Integrate with the Xcode debugger for text and graphics

Two-Way Text Comparison & Merging
- Three powerful display modes
- Super-fast diffing of lines and character-level changes
- Color coding to spot added, deleted, and changed text

Three-Way Merge
- Review code changes and resolve conflicts
- Intelligently auto-merge the right content

File & Folder Comparison
- Ultra-fast algorithm for finding differences in large folders
- Sort and filter down to what matters most
- Drill deeper into folders for more detailed comparisons
- Copy your preferred files across sources

Powerful Image Comparison
- Compare images side by side, stacked, or split
- Spot subtle pixel differences with a high contrast “difference mask”

Optimized for macOS
- Beautiful, modern UI made to feel at home on your Mac
- Full-screen mode for focusing on your content
- Looks gorgeous on retina displays and works wonderfully with high-resolution graphics


"Kaleidoscope epitomizes the concept of “versatile software”: anyone can pick it up and use it, and the app will “scale” according to a user’s needs." - Federico Viticci,

"Kaleidoscope 2 is breeze. I wish I'd had something like Kaleidoscope when I wrote my first novel, and I'll be counting on it when I finally get around to writing the next one." - Rene Ritchie,

"It’s beautifully designed, fast and wonderful to use. It’s become an essential part of my toolkit already." - Matthew Panzarino, The Next Web

"The new Kaleidoscope is great, and has awesome and committed people behind it. Devs and designers need this tool." - @SteveStreza

"I just bought Kaleidoscope app! It has already saved my time greatly once (by comparing SQL from clipboard). Thank you!" - @befive_info

"Kaleidoscope 2 is the best merging tool for the Mac, hands down. I finally don't miss BeyondCompare." - @stefankendall


If you have any questions or feedback about Kaleidoscope, please contact us at
Learn about important Kaleidoscope updates and announcements by following @kaleidoscopeapp on Twitter.

What’s New

Version 2.4.1

While we are working on bigger things (to be announced soon), this intermediate update fixes a few issues discovered after the 2.4 release. It makes the Xcode debugger integration even easier to use and more powerful. Please contact us when running into problems or suffering from missing features (Help > Send Feedback…). We also love seeing positive reviews and mentions on the interwebs.

• The kspo command, accessible from lldb, gained a few new superpowers:
· macOS developers: Send a visual representation of any NSImage, NSView, or NSWindow to Kaleidoscope just by using kspo [object]
· iOS developers: Send a visual representation of any UIImage or UIView (which also means UIWindow) to Kaleidoscope just by typing kspo [object]
· If you prefer the old way of seeing a textual description, state that by typing kspo [object].description
• Single page PDFs such as your typical graphic assets for development are now being rendered as images, enabling visually comparing of those files.
• Added support for ~/.config directory location (XDG) for git integration configuration
• Fixed a case where your ~/.gitconfig could be overwritten when using the Configure button for the git integration.
• When using ksdiff (available as a separate download from within the app), the —no-wait option was sometimes ignored.

Ratings and Reviews

3.8 out of 5
46 Ratings

46 Ratings

Ellen Teapot ,

Excited to see new updates for a great tool

New ownership! New releases! How exciting! This long-time Kaleidoscope user thinks the future looks bright. (Maybe a bit too bright? Looking forward to dark mode support in a future update.)

Collin Donnell ,

The best by far

I've been a fulltime developer for over a decade, tried other tools, and there's just nothing else that comes close to Kaleidoscope.

Something I love about it versus the alternatives is that it's often able to fix conflicts automatically that my source control system was not, and so just launching Kaleidoscope app fixes the problem without me doing anything.

Also it looks really good. I don't think anyone ever asked for a merge tool needed to be pretty, but it is, and it makes using anything else totally unpalatable.

AidinK ,

Great Idea but not optimized to actually work.

I love the idea of this app and UI/UX design but sadly the app crashes too often & everytime you press copy and try to actually run the task.
So I now just use it as a visual checker and manually transfer on Finder which then it really makes this app not worth the money. I’m still willing to wait and give it a chance but you MUST work on the backend to fix these crashes and review the crash reports plz.

One thing i would like added is a progress bar or a Que to see that status of individual tasks or all tasks. PLEASE fix the crashing issues.
Working on an iMac Pro just FYI if that helps.

App Privacy

The developer, Letter Opener GmbH, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Linked to You

The following data may be collected but it is not linked to your identity:

  • Identifiers
  • Usage Data
  • Diagnostics

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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