Purrchiver reads a wide range of archive formats and creates the common ones. The complete matrix is below, grouped by category.
In the Create column: ✓ = free to create, 🔒 = creating it is part of the one-time $9.99 unlock, — = Purrchiver doesn’t author this format. Reading and extracting every format is always free. See What’s free vs. the unlock for the full breakdown, and note that any encryption or split-volume output is part of the unlock regardless of format.
Create vs. edit. “Create” means authoring a brand-new archive of that format. A few formats Purrchiver can’t create can still be edited in place once opened — adding/removing entries and saving. That’s true of the ZIP-based app bundles IPA and APK, plus every format already marked editable. See Editing an existing archive for the full edit-in-place list.
If you’re searching for a specific format and it’s not listed here, see What’s not supported at the bottom — it may be an intentional skip with a documented reason.
How Purrchiver does it
Purrchiver picks an engine per format:
- libarchive (BSD-2 license) — the primary engine, handles most formats.
- UnRAR (RarLab freeware, read-only permitted) — handles encrypted RAR.
- LZMA SDK (public domain) — handles encrypted 7z (AES-256).
- AppleArchive (Apple system framework) — handles AAR (Apple Archive) and AEA (Apple Encrypted Archive).
- libbrotli (vendored Brotli 1.1.0
reference library, MIT license) — handles Brotli (
.br/.tar.br). - age (vendored) — the universal passphrase encryption wrap.
These are vendored libraries inside the app bundle — no 7zz / unar
subprocess. The one exception is creating a .dmg, which uses Apple’s
own hdiutil (the sandbox-safe, Apple-supported way to build a disk
image). The app stays self-contained and sandboxed.
Common formats
| Format | Read | Create | Notes |
|---|---|---|---|
| ZIP | ✓ | ✓ | The default for most use. Cross-platform safe. Archives > 4 GB use the ZIP64 extension automatically. |
| ZIP + AES-256 | ✓ | 🔒 | Modern, secure ZIP encryption. The default when encrypting ZIPs. |
| ZipCrypto ZIP | ✓ | — | Legacy ZIP encryption — Purrchiver reads these but won’t write them (see why). |
| IPA / APK | ✓ | — | iOS / Android app bundles (ZIP under the hood). Detected and labeled; extract, inspect, and edit in place — but Purrchiver doesn’t author new ones. |
| JAR / WAR / EAR | ✓ | — | Java archives. Detected and labeled (not generic ZIP); read + inspect. Creation is owned by the JDK toolchain. |
| RAR4 | ✓ | — | Older RAR. RAR can’t be written by third-party tools per RarLab’s license. |
| RAR5 | ✓ | — | Modern RAR. Same restriction on writing. |
| Multi-part RAR | ✓ | — | Both .partN.rar and legacy .r00/.r01/… schemes. See Multi-part archives. |
| Encrypted RAR | ✓ | — | Both content-encrypted and header-encrypted. |
| .crypto | ✓ | — | MacPaw Encrypto (MPE1) — AES-256, integrity-checked. Purrchiver prompts for the password (showing Encrypto’s stored hint, if any), decrypts, and lets you browse and extract the contents like any archive. Read-only — Purrchiver never creates .crypto. |
| 7z | ✓ | 🔒 | Best compression. Good for personal archives. |
| 7z + AES-256 | ✓ | 🔒 | Modern, secure 7z encryption. Write-path encrypts file contents; filenames in the archive listing remain visible. Header-encrypted 7z is read-supported. |
| tar | ✓ | ✓ | POSIX, ustar, pax, GNU variants all readable. Bare, uncompressed .tar is also a write/output format — for already-compressed payloads or fast bundling. |
| .tar.gz | ✓ | ✓ | Standard Unix gzipped tar. |
| .tar.bz2 | ✓ | ✓ | bzip2-compressed tar. |
| .tar.xz | ✓ | 🔒 | xz-compressed tar. |
| .tar.zst | ✓ | 🔒 | Zstandard-compressed tar. Modern, fast. |
| .tar.lz | ✓ | 🔒 | lzip-compressed tar. |
| .tar.lz4 | ✓ | 🔒 | LZ4-compressed tar. Fast; good for transient / backup archives. |
| .tar.br | ✓ | 🔒 | Brotli-compressed tar. |
gzip (.gz) | ✓ | ✓ | Single-stream. |
bzip2 (.bz2) | ✓ | ✓ | Single-stream. |
| xz | ✓ | 🔒 | Single-stream. |
Zstandard (.zst) | ✓ | 🔒 | Single-stream. Modern, fast. |
Brotli (.br) | ✓ | 🔒 | Web tooling (nginx, Cloudflare, npm). Via the vendored libbrotli reference library (MIT). |
LZMA (.lzma) | ✓ | 🔒 | Predecessor to xz; still in some legacy Linux tarballs. |
| ISO 9660 | ✓ | 🔒 | Includes Joliet + Rock Ridge extensions. Data ISOs only — bootable ISOs aren’t supported (use Finder to mount). |
| DMG | ✓ | ✓ | Open, extract, and drag out a disk image’s contents like any archive. Plain .dmg is free to create; built via Apple’s hdiutil. |
| DMG + AES-256 | ✓ | 🔒 | Encrypted disk image. Purrchiver prompts for the password and browses/extracts it in-app; creating one is part of the unlock. |
Apple ecosystem
| Format | Read | Create | Notes |
|---|---|---|---|
| AAR (Apple Archive) | ✓ | ✓ | Apple’s native format. Writes with LZFSE (Apple’s default). macOS 11+. |
| AEA (Apple Encrypted Archive) | ✓ | 🔒 | Apple’s encrypted archive format — always encrypted. To create one, pick AAR in the Create Archive sheet and set a password; Purrchiver writes .aea instead of .aar. Apple requires the password to be at least 32 ASCII characters (Unicode passwords land in v1.1). It’s a standard Apple format — macOS’s built-in aa command can create and open the same password-encrypted .aea, so it’s interoperable, not Purrchiver-specific. Opens on Apple platforms only. |
| age wrap | ✓ | 🔒 | Universal passphrase encryption — wrap any container or file (.tar.zst, .iso, .aar, a single-stream file…) into a <name>.age envelope no other Mac archiver offers. Decrypts to a sibling. See Encrypted archives. |
| XIP | ✓ | — | Apple Signed Archive. Extracts contents without verifying Apple’s signature (use Apple’s installer for signature-trust workflows). |
| PKG | ✓ | — | Apple flat-package installer. Read-only inspection — Apple’s pkgbuild / productbuild own creation. |
| MPKG | ✓ | — | Apple meta-package (multi-pkg installer). Same as PKG above. |
| XAR | ✓ | — | The container used by PKG/MPKG. Standalone read supported. |
Unix & Linux
| Format | Read | Create | Notes |
|---|---|---|---|
| CPIO | ✓ | 🔒 | POSIX + SVR4 variants. Same engine that drives XIP. |
.deb | ✓ | — | Debian package via ar. Read-only peek-inside for Mac devs working with Linux containers. |
.rpm | ✓ | — | Red Hat package peek-inside. |
.a (static library) | ✓ | — | Standalone ar static libraries — read-only listing/extract (ar -t libfoo.a territory). |
.lz (lzip) | ✓ | 🔒 | GNU archival / scientific use. |
.lz4 | ✓ | 🔒 | LZ4 frame-format streams. |
Legacy & archival
| Format | Read | Create | Notes |
|---|---|---|---|
| LHA / LZH | ✓ | — | Japanese / retro-Mac legacy. |
| CAB | ✓ | — | Microsoft Cabinet. Older Windows install media. |
| WARC | ✓ | — | Web Archive (Internet Archive crawl format). |
.Z (compress) | ✓ | — | Legacy Unix .Z archives — read-only restoration. |
What’s not supported
These are intentional skips. The reason is given for each. The Legacy & niche formats page goes deeper on the “detected but not extracted” formats and tells you what to use instead.
| Format | Why not |
|---|---|
| RAR (write) | RarLab’s UnRAR source license forbids creating RAR encoders from the UnRAR sources. A clean-room reimplementation would be legally permissible but goes against RarLab’s stated wishes — we honor both. Read-only is explicitly permitted and fully supported. |
StuffIt (.sit, .sitx) | Dead format, abandoned by Smith Micro. Detected; friendly error. See StuffIt files. |
| ACE | Proprietary, no clean OSS reader, documented malware-vector history. Detected; friendly error. See Legacy & niche formats. |
| ARJ | Long-tail DOS-era legacy. Not in libarchive. Not worth a bespoke reader. |
BinHex (.hqx) / MacBinary (.macbin) | 1990s Mac transport encodings. Detected; friendly error pointing to The Unarchiver. See Legacy & niche formats. |
| LZO / LRZIP / grzip | Niche Linux compressors with GPL-2 libraries that bring MAS-distribution friction not worth it for the user count. Detected; friendly error pointing to CLI tools. See Legacy & niche formats. |
.exe self-extractors | Windows installers, not archives. Detected; friendly error. |
If a format isn’t in the matrix above and isn’t on the “What’s not supported” list, Purrchiver doesn’t handle it. Email corey@purrchiver.app if a missing format is blocking your workflow — user demand is the signal for what to add.
Searching by extension
If you’re searching by extension, you’ll find it in the chip list above under the appropriate category.