Kotej
Compare folders, ZIP and JAR
Only for Mac
Free · In‑App Purchases
Mac
Kotej compares two folders, two files or two builds of an artefact and shows you, at a glance, what actually changed.
ARCHIVES ARE FOLDERS
A ZIP, a JAR, an EAR or a WAR opens and browses like a directory, with nothing to unpack by hand. Nested too: an EAR holding JARs holding classes is walked all the way down. Comparing the artefacts of two builds stops being an afternoon's work.
JSON AND XML BY MEANING, NOT BY FORMATTING
Two JSON files with the keys in a different order, or two XML files reindented, mean the same thing: Kotej marks them equivalent instead of painting the whole tree red. And when what you need is exactness, you ask for byte for byte.
THREE MODES, AND THE RIGHT ONE BY DEFAULT
• Byte for byte: any differing bit counts.
• Text: tolerates line endings, trailing spaces, case or blank lines, as you prefer.
• Semantic: JSON and XML that are equivalent even when the bytes differ.
Every file gets the mode that suits its type automatically, and you can force another one whenever you want.
FROM DIAGNOSIS TO ACTION
A side-by-side tree with an "only differences" filter. A line-by-line file diff that points at the exact characters that changed. Navigation between differences from the window toolbar. And copying from one side to the other once you know which one is right. When you have to explain it, export the comparison as Markdown or JSON, or copy it ready to paste into an AI chat.
SEVERAL COMPARISONS AT ONCE
Each tab is an independent comparison, with its own state and options. Reopen the app and they are still there.
IN THE FINDER MENU
Select two items and pick "Compare the 2 items with Kotej". Or mark one with "Select for comparison" and choose the other later, even from a different window.
FAST BECAUSE IT READS ONLY WHAT IT MUST
A ZIP's central directory already carries the CRC32 and size of every entry, so two identical JARs are settled without decompressing a single byte. Only the content needed to decide is ever read.
YOUR FILES NEVER LEAVE YOUR MAC
Kotej works offline and without an account. It runs inside the macOS sandbox, requests no network access and collects no data: what you compare stays where it is.
Interface in English and Spanish. Requires macOS 14 Sonoma or later.
Free to download with a 14-day trial of every feature, then a one-time purchase to keep it. No subscription, and nothing is ever charged automatically. The same engine also has a free web version at kotej.alexandre-vazquez.cloud, which compares inside your browser without uploading anything.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Try Kotej free for 14 days. Kotej becomes a free download with a 14-day trial of every feature, then a one-time purchase to keep comparing. No subscription: nothing is ever charged automatically.
- If you already bought Kotej, there is nothing to do: it unlocks by itself. If it does not, "Restore purchases" unlocks it.
- During the trial, the tab bar shows the days left and lets you buy at any time (also from the Kotej > Buy Kotej… menu).
- When the trial ends, new comparisons are locked until you buy. Open tabs are kept.
The developer, Alexandre Vazquez, 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 Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Alexandre Vazquez
- Size
- 1.5 MB
- Category
- Developer Tools
- Compatibility
Requires macOS 14.0 or later.
- Mac
Requires macOS 14.0 or later.
- Mac
- Languages
- English and Spanish
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- 14-Day Trial $0.00
- Kotej Full Unlock $8.99
- Copyright
- © 2026 Alexandre Vazquez