This is the PREVIOUS VERSION of Kaleidoscope. Please DO NOT BUY, unless you can't update your computer to macOS Big Sur. Look for Kaleidoscope 3 instead.


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 2.4.5

* New first screenshot
* Minor fixes

Ratings and Reviews

4.2 out of 5
108 Ratings

108 Ratings

CdrSpock ,

A little pricey, but certainly powerful

I'd heard about Kaleidoscope many times before deciding to buy it. It always seemed like a handy thing to have around, but the price tag made me hesitate. Eventually, I found myself in a situation where I needed to compare lots of folders on external drives to figure out what was different between two backups, so I bit the bullet.

What's really striking to me is that from a computational perspective, comparing text, images, and directory structures are fundamentally different tasks. Despite that, Kaleidoscope handles them all, and it does so very elegantly. I'll definitely be keeping it around.

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.

Will It Work ,

A solid utility tool

While Kaleidoscope is idiosyncratic in several ways, it is powerful and full-featured; it competently serves as a good visual diff.

I don't use the integrations, so I can't speak to them, but the multiple comparison sets, and being able to compare images and text in the same utility, and navigate repos makes maintaining projects or just working with casual tasks easy.

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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