7-Zip File Manager

7za, 7z, 7Zip, Archiving, Archives, Compression, File Browser

7-Zip Archiving and File Management Utility

Create and manage archives with one of the variations of 7-Zip available in a command-line version for Linux/Mac (P7Zip), and for Windows (7za) as well as a graphical user interface version for Windows (7Zip). Although its interface is deceptively simple, the command-line versions of 7ZIP are highly customizable archiving programs when used with the command parameters and switches described in the Command-line Guide.  Windows users who want to use the command-line version should generate a Help Desk ticket to install the standalone 7za.exe version.

While offering fewer customization options, the GUI version of 7-Zip for Windows maximizes ease-of-use by providing a management console that enables files to be manipulated in place with a few clicks of the mouse.

7-Zip Supported File Formats

Additional supported file formats for decompressing may be possible.

Format Compressing Decompressing Filename Extensions
7z X X 7z
BZIP2 X X bz2 bzip2 tbz2 tbz
GZIP X X (compress, pack, zip)
gz gzip tgz
LZMA X X lzma
MSI X X msi
PDF X X pdf
TAR X X tar
WIM X X wim swm
XZ X X xz
ZIP X X zip
X arj
X cab
X chm chw hxs
X msi doc xls ppt
X cpio
X cramfs
X deb
X dmg
X fat
X hfs
X iso
X lzh lha
X mbr
X exe
X ntfs
X rar
X rpm
X 001 002 ...
X squashfs
X udf
X vhd
X xar
X z taz tar.z


Archive Specifications in 7-Zip

Archive Format: Specifies a format of created archive. Some formats (gzip and bzip2) do not support compressing more the one file per archive.

Compression Ratio: Compression ratio results are very dependent upon the data used for the tests. Usually, 7-Zip compresses to 7z format 30-70% better than to zip format. And 7-Zip compresses to zip format 2-10% better than most of other zip compatible programs.

Compression Level: Specifies compression level. There are 6 levels of compression:

Value Meaning
Store Files will be copied to archive without compression.
Fastest Fastest compression.
Fast Fast compression.
Normal Compression with balanced settings.
Maximum Can give a higher compression ratio than Normal level. But it can be slower, and it can require more memory.
Ultra Can give a higher compression ratio than Maximum level. But it can be slower, and it can require more memory.

Compression Method: (see below for additional details) Specifies the compression method.

Dictionary Size: Specifies Dictionary size for compression method. Usually, a higher Dictionary size gives a higher compression ratio. But compressing can be slower and it can require more memory. Memory (RAM) usage for LZMA compressing is about 11 times more than dictionary size. Memory usage for LZMA decompressing is close to value of dictionary size. Memory usage for PPMd compressing and decompressing is almost equal to dictionary size.

Word Size: Specifies the length of words, which will be used to find identical sequences of bytes for compression. Usually for LZMA and Deflate, big Word size gives a little bit better compression ratio and slower compression process. A big Word size parameter can significantly increase compression ratio for files which contain long identical sequences of bytes. For PPMd, the Word size strongly affects both compression ratio and compression/decompression speed.

Solid Block Size: Specifies the size of a solid block. You can also disable solid mode. In solid mode all files will be compressed as continuous data blocks. Usually compressing to a solid archive improves the compression ratio. You can use this option only for 7z archives. With the current version of 7z, you can update existing archives only when solid mode is switched off and the existing archive is non-solid.

Number of CPU Threads: Specifies the number of threads for compressing. A big number of threads can speed up compression speed on Multi-Processor systems. Sometimes it can increase speed even on single-core CPU.

Split to Volumes: Parameters - {Size}[b | k | m | g] Specifies volume sizes in Bytes, Kilobytes (1 Kilobyte = 1024 bytes), Megabytes (1 Megabyte = 1024 Kilobytes) or Gigabytes (1 Gigabyte = 1024 Megabytes). If you specify only {Size}, 7-zip will treat it as bytes. It's possible to specify several values. Eg; 10k 15k 2m creates three volumes; 10KB, 15KB, and 2MB in size.

Options: Create SFX archive - Creates a self-extracting archive with the -sfx switch.

Encryption: 7-Zip supports AES-256 encryption for archiving in the 7z and ZIP formats as well as ZIPCrypto in the ZIP format. AES-256 provides the strongest encryption but is only supported by 7-Zip, WinZip and a few other archivers, so if compatibility is a concern, use the ZIP format with ZIPCrypto encryption.

Parameters: Allows you to specify parameters for compression. See the -m (Method) switch description for more details. Omit the -m prefix (as in -m switch) when using this dialog box. Eg; 0=PPMd specifies the PPMd method for compressing files. Eg; 0=bcj2 1=lzma:d23 2=lzma 3=lzma b0:1 b0s1:2 b0s2:3 specifies the BCJ2 filter (for x86 executables) and LZMA as the compression method.

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