A free Kaleidoscope alternative
you don't have to rent.

Kaleidoscope is a beautiful, native Mac diff app, and it's sold as a subscription. Twofold is native and polished too, but free and open source. Here's how they honestly compare.

Download Twofold free See all features

macOS 26 or later · Apple silicon & Intel · Open source, GPLv3

Twofold comparing two versions of a Swift file

Twofold vs Kaleidoscope at a glance

Twofold Kaleidoscope
Price Free (4,99 € once on the App Store, later) Subscription
Open source ● GPLv3 No
Native macOS app ● Yes ● Yes
Account or license needed ● None Yes
Text file comparison ● Yes ● Yes
Folder comparison ● Yes ● Yes
Word-level highlights ● Yes ● Yes
git difftool ● Yes ● Yes
Merge and edit On the roadmap ● Yes
Three-way merge On the roadmap ● Yes
Image diff On the roadmap ● Yes

Kaleidoscope is a trademark of its owner. Pricing and features as we understand them; check the vendor for current details.

Where Twofold is better

  • ✓It's free, for good. No subscription, no license key, no account. The GPL means nobody can take it away or put it behind a paywall later, not even us.
  • ✓Fluid layout. Changes on each side are joined by curves through the middle, and both sides glide so the change you're reading stays lined up, without filler lines.
  • ✓Fast on big files. 100,000 lines diff in under 60 ms, and scrolling stays at 120 Hz.
  • ✓Nothing phones home. No telemetry, no license server.

Where Kaleidoscope is better

  • –Merging. Kaleidoscope merges and edits; Twofold v1 only shows differences. Copying changes between sides is next on the roadmap.
  • –Images and three-way merge. If you diff images or resolve git conflicts in a GUI, Kaleidoscope does both today.
  • –Older macOS. Twofold needs macOS 26 or later.

Should you switch?

If you mostly open a diff to read what changed, in code review, after a git pull, or between two exports, Twofold covers that well and costs nothing. If you merge conflicts in a GUI every day, stay with Kaleidoscope for now, and keep an eye on our roadmap.

Download Twofold free

Questions

Is Twofold a good free alternative to Kaleidoscope?

For reading diffs of text files and folders, yes. Twofold is native, polished and free. Kaleidoscope still does more, including merging, image diff and three-way merge.

Can I use Twofold as git difftool like ksdiff?

Yes. Install the twofold command with make install and set it as your diff.tool. git difftool --dir-diff opens a whole tree in one window.

Does Twofold have a subscription?

No, and it never will. It's free from GitHub. The planned Mac App Store version is a single 4,99 € purchase.