How to Open 7z Files on Mac, Including Password-Protected Ones

A 7z file is an archive made with 7-Zip, usually compressed with LZMA or LZMA2 and optionally encrypted with AES-256.

Like a ZIP, it bundles files and folders into one file. It often packs them smaller, and its encryption can hide the file names as well as the contents, which ZIP can't. That extra protection is also why some extractors can't open every 7z you receive.

On recent versions of macOS, double-clicking a .7z file opens it in Archive Utility, which extracts it into a folder next to the archive.

If your Mac says it can't open the file, Terminal can: type tar -xf followed by a space, drag the archive onto the Terminal window and press Return. The tar command that ships with macOS reads 7z archives and extracts them into the current folder, which is your home folder in a new Terminal window.

Neither route can extract a password-protected 7z archive. For those, and for archives you don't fully trust, you need an extractor that handles 7z encryption.

File Acture's Extract Archive unpacks 7z, ZIP, TAR, gzip, bzip2 and xz archives (.tar.gz, .tgz, .tar.bz2, .tar.xz and single .gz, .bz2 and .xz files), with or without a password. It also opens split archives such as archive.7z.001.

For encrypted archives, type the password in the Password field. File Acture opens 7z archives encrypted with AES-256, including those whose file names are hidden, and ZIPs encrypted with AES or the older ZipCrypto. It checks the file's contents rather than trusting its extension, so a 7z archive saved with a .zip name still extracts, and you can unpack several archives in one run.

Each archive becomes a new folder in Documents › File Acture › Archives, or next to the archive if you choose Same folder as original. When everything sits in one top-level folder, that folder is the result; otherwise the folder is named after the archive. Mac clutter such as __MACOSX folders and ._ files is skipped.

A split archive is one archive cut into numbered parts, such as archive.7z.001, archive.7z.002 and so on, often to fit a size limit. Put all the parts in one folder and add any one of them to Extract Archive: File Acture joins the set by itself, so you don't have to merge the parts first.

The parts of one set show up as a single item in the list. ZIP and TAR archives split the same way (archive.zip.001, archive.tar.xz.001) work too. If a part is missing, File Acture shows an error instead of extracting an incomplete archive.

To list a plain 7z archive's contents without extracting it, type tar -tf followed by a space in Terminal, drag the archive onto the window and press Return.

Archive Utility doesn't show a preview; it just extracts. Extract Archive unpacks the whole archive into a new folder, which you can open with Show in Finder and delete if it isn't what you wanted.

An archive can't run anything by itself, but a crafted one can try to write files outside the folder you extract to, or unpack into far more data than it looks like.

File Acture refuses archives whose entries point outside the destination with absolute paths or .. steps, skips symbolic links, never applies set-user-ID permissions, and stops an extraction that would grow past roughly 50 GB or 200,000 entries. Everything is unpacked into a hidden staging folder first, so a damaged or cancelled archive leaves nothing half-extracted. And unlike an online extractor, it never uploads the archive.