Ajar, a Mac app from Foundry Tabor
Open any archive like a folder.
Ajar is a fast, careful archive utility for the Mac. Browse ZIP, 7z and tar archives without unpacking them, take out just the files you need, and make archives that open anywhere.
In testing now. Coming to the Mac App Store for Macs with Apple silicon, on macOS 15 or later.
Simple like Archive Utility. Capable like 7-Zip.
Ajar opens and makes the formats people actually send, and keeps the everyday case to a double-click.
Browse without unpacking
An archive opens like a folder. Expand what you need, press Space to Quick Look a file, or double-click to open it.
Take only what you need
Extract everything beside the archive, or select a few files and drag them to Finder. Progress and Cancel stay in the window.
Change archives in place
Drag files in, rename with Return, delete, or move items between folders in ZIP, 7z and tar archives, without unpacking and repacking.
Make archives that open anywhere
ZIP by default, so Windows and Finder can open it. 7z when you want the smallest file, and split into parts when there's a size limit.
Passwords that mean something
AES-256 for ZIP and 7z, and 7z can hide file names too. Ajar can remember passwords in your Keychain.
Right from Finder
Right-click files for Compress with Ajar, or archives for Extract Here with Ajar.
It tells you what a choice costs.
Making an archive takes one sheet: a name, a format, and options if you want them. Ajar says plainly what each choice means, like whether Windows can open the result.
That includes the uncomfortable parts. ZIP encryption leaves file names readable and its passwords are much cheaper to guess, so Ajar says so, and points you to 7z with hidden names for anything sensitive.
What Ajar opens and makes.
| Format | Open | Create | Details |
|---|---|---|---|
| ZIP | Yes | Yes | Deflate, Zstd, xz, Bzip2 or stored; AES-256; compressed on all cores |
| 7z | Yes | Yes | LZMA2, solid archives; AES-256 with hidden file names |
| tar | Yes | Yes | Plain, or with gzip, bzip2, xz, zstd or lz4 |
| .gz .bz2 .xz .zst .lz4 | Yes | Yes | Single compressed files |
| Split archives | Yes | Yes | Open from any piece: numbered parts (.001) from 7-Zip, Keka or Ajar, and spanned ZIPs from WinZip |
Ajar doesn't open RAR files. ISO, cab and other read-only formats are planned after version 1.
Archives are untrusted. Ajar treats them that way.
Anything you download can be built to attack the program that opens it. Ajar is designed so a hostile archive has nowhere to go.
How it protects you
- Archives are decoded in a separate, sandboxed reader with no access to your files. If it crashes, Ajar says so and carries on
- Nothing lands outside the folder you chose: paths with
..and symlinks that lead out are refused - Gatekeeper still checks what you extract, and Ajar shows apps and scripts in Finder instead of opening them
- Zip bombs stop early, and free space is checked before extracting
- A failed or cancelled extraction leaves nothing half-done
- Ajar collects no data at all: no analytics, no tracking
A Rust engine, on every core.
Ajar's archive engine is written in Rust and compresses in parallel. The app around it is native SwiftUI and AppKit, built for Apple silicon.
Compressing a 259 MB folder of 8,000 files on an M-series Mac: tar.xz in 8.1 s against 37.7 s, ZIP in 1.8 s against 5.7 s.
The same engine in Terminal.
Ajar also comes as a command-line tool, ajar, on its way to Homebrew.
ajar create Photos.zip ~/Pictures/Trip
ajar list Photos.7z --tree
ajar extract Photos.7z '*.jpg' -o ~/Desktop
ajar create Photos.7z Trip --split 100MOpen source, and on the App Store.
Ajar's source will be public on GitHub under the Apache-2.0 license when version 1 ships. The Mac App Store version is paid, which is how the work gets funded.
Hear when Ajar is out.
Ajar is made by Foundry Tabor, the same practice that builds software for clients.