Overview
7-Zip is three megabytes and it does more than archivers a hundred times its size. It reads and writes 7z, zip, tar, gzip, bzip2, xz and wim, and it reads rar, cab, iso, msi, deb, rpm, dmg, vhd, squashfs and a long list of others, which in practice means anything you are handed opens. The 7z format with LZMA2 compresses tighter than zip by a wide margin, and on text or source archives the difference is not subtle.
There is no license to handle here, no trial, no bundled offers and no background service. It installs a shell menu, a file manager and a command line tool and then leaves the machine alone. The 26 release brings the improved multithreading through to more of the codec paths, so on a machine with a lot of cores a large archive compresses noticeably faster than it did.
Compression that is worth the wait
The 7z format defaults to LZMA2, with dictionary sizes up to a gigabyte if you have the memory to spend. On a folder of documents or source code the result is routinely thirty to fifty percent smaller than the same folder as a zip. Solid archiving compresses files as one continuous stream, which helps enormously on many small similar files and is the reason a source tree packs so well.
The tradeoff is that a solid archive has to be partly decompressed to pull one file out of the middle, so for an archive you will be reaching into constantly, turn solid mode off. Compression level runs from store through ultra, and ultra on a large dictionary will use several gigabytes of memory while it works. The estimate is shown before you start.
Formats, splitting and encryption
Archives can be split into volumes of any size, which is still the practical way to move something large across a medium that will not take one big file. Self extracting archives can be created for 7z, producing an executable that unpacks without the program installed at the other end.
Encryption uses AES with a 256 bit key, and for 7z archives the file names inside can be encrypted as well as the contents, so the listing does not leak what is in there. This is real encryption rather than the weak legacy zip scheme, and there is no recovery if the passphrase is lost.
Shell integration and the file manager
The context menu is the part everyone actually uses: extract here, extract to a named folder, add to an archive, and the compress and email entries. On Windows 11 the entries appear in the modern menu as well as the classic one, so the extra click is not needed.
The bundled file manager is a plain two pane browser that treats archives as folders. You can open an iso, drag one file out, or move something into an existing archive without unpacking it first. The benchmark tool in there is also the quickest honest way to compare two machines, since it measures exactly the kind of work everyone actually does.
Command line use
The console version takes the same options as the graphical one and is the right tool for scripted backups and build steps. Adding, updating, extracting with paths, testing integrity and listing contents are all one line each, exit codes are meaningful, and it handles very long paths correctly, which is more than can be said for a lot of tools.
Archive testing deserves a mention on its own. Running a test pass over an archive verifies every stream against its checksum, which is the cheapest way to find out that a backup has quietly rotted before you need it.
What you get
- 7z format with LZMA2 and dictionary sizes up to a gigabyte
- Reads rar, iso, cab, msi, deb, rpm, dmg, vhd, wim and many more
- Solid archiving for high ratios on many small files
- AES 256 encryption including encrypted file name listings
- Split archives into volumes of any size
- Self extracting archive creation
- Shell menu on both the classic and modern Windows context menus
- Two pane file manager that browses archives as folders
- Console version with meaningful exit codes for scripting
- Integrity test pass over any supported archive
- Built in benchmark
Inside the archive
- 7-Zip installer for x86, x64 and ARM64
- Console version
- Shell extension
- Interface language files
- Readme covering the portable option
System requirements
| Operating system | Windows 10 or Windows 11, any architecture listed |
|---|---|
| Processor | Anything, more cores compress faster |
| Memory | Minimal, unless you use very large dictionaries |
| Graphics | Not used |
| Storage | 20 MB |
| Permissions | Administrator for the shell menu registration |
Installing it
- Unpack and run the installer for your architecture.
- Accept the default install path so the shell menu registers cleanly.
- Open a folder and check that the context menu entries are present.
- Set 7-Zip as the handler for the archive types you want in its own options panel, not in Windows settings.
- If you prefer no shell integration, the portable folder in the archive runs without installing.
Mirrors
| Route | Region | Note | State |
|---|---|---|---|
| Direct, primary | Europe | No wait, resumable | Online |
| Direct, secondary | North America | No wait, resumable | Online |
| Torrent magnet | Global | Not needed, file is tiny | Online |
Release history
- Multithreading extended to more codec paths
- Fixed extraction of some large split rar sets
- Reduced memory use during solid archive creation
- New format handlers added
- Faster zip extraction on many small entries
- ARM64 native build
- Long path handling corrected in the console version
Questions about this release
Can it create rar archives?
No. It reads rar perfectly well but the format is proprietary and only its own tool writes it.
Which format should I use?
7z if the person at the other end can open it, which is nearly everyone. Zip if you cannot be sure, since every system opens zip natively.
Is the encryption trustworthy?
AES 256 as implemented here is sound. There is no back door and no recovery, so a forgotten passphrase means the archive is gone.
Why is ultra compression so slow?
It is searching a very large window for matches. That is where the ratio comes from. Use normal for everyday work and save ultra for archives you will keep.
Comments
Sixteen cores and the new build actually uses them now. Half the time on a big archive.
Portable folder on a stick, opens every weird format the office throws at me.
Comments are read before they appear. If a build stops working, say so here and it gets rebuilt rather than quietly left up.
Packed a 40 GB source tree solid and it came out under 6. Nothing else gets close.