View source for 7-Zip

{{Short description|Open-source file archiver}}
{{Use dmy dates|date=June 2014}}
{{Infobox software
| name = 7-Zip
| logo = 7ziplogo.svg
| screenshot = 7-Zip.png
| caption = 7-Zip File Manager on [[Windows 11]]
| developer = Igor Pavlov<ref name="dobb">{{cite web |url=https://www.drdobbs.com/dr-dobbs-data-compression-newsletter/184405338 |title=A Few Questions for Igor Pavlov |date=2003-04-30 |publisher=[[Dr. Dobb's]] Data Compression Newsletter |access-date=2023-03-28}}</ref>
| released = {{Start date and age|1999|7|18|df=yes}}<ref name="7zipHistory">{{cite web |url=https://7-zip.org/history.txt |title=History of 7-zip changes |publisher =7-Zip 20.02 alpha |date=8 August 2020|access-date=8 August 2020}}</ref>
| latest release version = <!-- Do not write here. It is managed in Wikidata. -->
| latest release date = <!-- Do not write here. It is managed in Wikidata. -->
| latest preview version = <!-- Do not write here. It is managed in Wikidata. -->
| latest preview date = <!-- Do not write here. It is managed in Wikidata. -->
| programming language = [[Assembly language|Assembly]], [[C (programming language)|C]] and [[C++]]<ref name="p7zip SourceForge">{{cite web | url =https://sourceforge.net/projects/sevenzip/ | title =P7ZIP SourceForge |date= January 2016 | website=[[SourceForge.net]] | access-date =2016-03-07 }}</ref>
| operating system = [[Windows]]/[[ReactOS]],<ref>{{cite web | url =https://www.reactos.org/wiki/Tests_for_0.4.14 | title = Tests for ReactOS 0.4.14}}</ref> [[BSD]], [[macOS]], [[Linux]],<ref name="7zip-linux"/>
| language count = 89
| language footnote = <ref>''Options...'' dialog box of 7-Zip for Windows 21.00 alpha</ref>
| language = <p>Afrikaans, Albanian, Arabic, Aragonese, Armenian, Asturian, Azerbaijani, Bangla, Bashkir, Basque, Belarusian, Breton, Bulgarian, Catalan, Chinese Simplified, Chinese Traditional, Corsican, Croatian, Czech, Danish, Dutch, English, Esperanto, Estonian, Extremaduran, Farsi, Finnish, French, Frisian, Friulian, Galician, Georgian, German, Greek, Gujarati, Indian, Hebrew, Hindi, Indian, Hungarian, Icelandic, Ido, Indonesian, Irish, Italian, Japanese, Kabyle, Karakalpak - Latin, Kazakh, Korean, Kurdish - Sorani, Kurdish, Kyrgyz, Latvian, Ligurian, Lithuanian, Macedonian, Malay, Marathi, Mongolian (MenkCode), Mongolian (Unicode), Mongolian, Nepali, Norwegian Bokmal, Norwegian Nynorsk, Pashto, Polish, Portuguese Brazilian, Portuguese Portugal, Punjabi, Indian, Romanian, Russian, Sanskrit, Indian, Serbian - Cyrillic, Serbian - Latin, Sinhala, Vietnam, Slovak, Slovenian, Spanish, Swedish, Tamil, Tatar, Thai, Turkish, Ukrainian, Uyghur, Uzbek, Valencian, Vietnamese, Welsh, Yoruba</p><p>These translations are partial and for the user interface only. Help and documentations are in English.</p>
| size = 1.1–1.7 [[Megabyte|MB]]<ref>{{cite web|title=7-Zip - Browse /7-Zip/16.00|url=https://sourceforge.net/projects/sevenzip/files/7-Zip/16.00/|website=[[SourceForge.net]]|publisher=Slashdot Media|access-date=12 May 2016|date=10 April 2016}}</ref>
| genre = [[File archiver]]
| license = [[GNU Lesser General Public License|LGPL-2.1-or-later]] with unRAR restriction<ref name=7zipdotorglicensetxt>{{cite web | url=https://7-zip.org/license.txt | title=7-Zip License for use and distribution | last=Pavlov | first=Igor |website=7-zip.org/ | year=2010 | access-date=2010-04-16 | archive-url= https://web.archive.org/web/20100410171656/http://www.7-zip.org/license.txt| archive-date= 10 April 2010 | url-status= live}}</ref> / LZMA SDK in the [[public domain]]<ref name="LZMA_SDK" />
}}
'''7-Zip''' is a [[free and open-source]] [[file archiver]], a utility used to place groups of files within compressed containers known as "archives". It is developed by Igor Pavlov and was first released in 1999.<ref name="7zipHistory" /> 7-Zip has its own archive format called [[7z]], but can read and write several others.
The program can be used from a Windows [[graphical user interface]] that also features shell integration, from a Windows [[command-line interface]] as the command <code>7za</code> or <code>7za.exe</code>, and from [[POSIX]] systems as <code>p7zip</code>.<ref name="p7ziphome">{{cite web | url =https://github.com/jinfeihan57/p7zip | title =P7ZIP |date= July 2022 | website =GitHub | access-date =2022-07-06 }}</ref> Most of the 7-Zip [[source code]] is under the [[GNU Lesser General Public License|LGPL-2.1-or-later]] license; the [[unRAR]] code, however, is under the [[GNU Lesser General Public License|LGPL-2.1-or-later]] license with an "unRAR restriction", which states that developers are not permitted to use the code to [[reverse-engineer]] the [[RAR (file format)|RAR]] compression algorithm.<ref>{{Cite web|url=https://www.7-zip.org/|title=7-Zip|last=Pavlov|first=Igor|website=7-zip.org|access-date=31 October 2012}}</ref><ref>{{Cite web|url=https://www.7-zip.org/license.txt|title=7-Zip – License for use and distribution|last=Pavlov|first=Igor|website=7-zip.org|access-date=31 October 2012}}</ref>
Since version 21.01 alpha, preliminary Linux support has been added to the upstream instead of the p7zip project.<ref name="7zip-linux">{{cite web |url=https://www.phoronix.com/scan.php?page=news_item&px=7-Zip-21.01-Initial-Linux |title=Upstream 7-Zip Adds Preliminary Linux Support |last=Larabel |first=Michael |date=2021-03-12 |publisher=Phoronix |language=en|accessdate=2021-03-17}}</ref>
==Archive formats==
===7z===
{{Main|7z}}
By default, 7-Zip creates 7z-format archives with a <code>.7z</code> [[file extension]]. Each archive can contain multiple directories and files. As a ''container'' format, security or size reduction are achieved by looking for similarities throughout the data using a stacked combination of filters. These can consist of pre-processors, [[Data compression|compression algorithms]], and [[encryption]] filters.
The core 7z compression uses a variety of [[algorithm]]s, the most common of which are [[bzip2]], [[Prediction by partial matching|PPMd]], [[Lempel–Ziv–Markov chain algorithm|LZMA2]], and [[Lempel–Ziv–Markov chain algorithm|LZMA]]. Developed by Pavlov, LZMA is a relatively new system, making its debut as part of the 7z format. LZMA uses an LZ-based sliding dictionary of up to 3840 MB in size, backed by a [[Range encoding|range coder]].<ref>{{cite web|last=Diaz|first=Antonio Diaz |title=Lzip|url=http://lzip.nongnu.org/lzip.html |website=LZip.NonGNU.org |access-date=29 July 2010| archive-url= https://web.archive.org/web/20100729135045/http://lzip.nongnu.org/lzip.html| archive-date= 29 July 2010 | url-status= live}}</ref>
The native 7z [[file format]] is open and [[Modular programming|modular]]. [[File name]]s are stored as [[UTF-16|Unicode]].<ref>{{cite web|url=https://www.7-zip.org/7z.html|title=7z Format|last=Pavlov|first=Igor|website=7-zip.org|access-date=16 April 2017}}</ref>
In 2011, [[TopTenReviews]] found that the 7z compression was at least 17% better than [[Zip (file format)|ZIP]],<ref>{{cite web|url=http://file-compression-software-review.toptenreviews.com/7-zip-review.html|title=7-Zip 2011 – TopTenREVIEWS|archive-url=https://web.archive.org/web/20121025200631/http://file-compression-software-review.toptenreviews.com/7-zip-review.html|archive-date=25 October 2012}}</ref> and 7-Zip's own site has since 2002 reported that while 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 other zip-compatible programs."<ref>{{cite web|url=http://www.7-zip.org/ |title=7-Zip (home page) |archive-url=https://web.archive.org/web/20020121054121/http://www.7-zip.org/ |archive-date=21 January 2002 |url-status=live |website=7-zip.org |author=Igor Pavlov }} Statement on compression performance very similar in January 2002 and April 2017.</ref>
The 7z file format specification is distributed with the program's source code, in the "doc" sub-directory.
===Others===
7-Zip supports a number of other compression and non-compression archive formats (both for packing and unpacking), including [[ZIP (file format)|ZIP]], [[gzip]], [[bzip2]], [[XZ Utils|xz]], [[tar (file format)|tar]], and [[Windows Imaging Format|WIM]]. The utility also supports unpacking [[Apple Partition Map|APM]], [[Ar (Unix)|ar]], [[ARJ]], [[Microsoft Compiled HTML Help|chm]], [[cpio]], [[deb (file format)|deb]], [[Flash Video|FLV]], [[JAR (file format)|JAR]], [[LHA (file format)|LHA/LZH]], [[Lempel–Ziv–Markov chain algorithm|LZMA]], MSLZ, [[Office Open XML]], [[onepkg]], [[RAR (file format)|RAR]], [[RPM Package Manager|RPM]], [[smzip]], [[SWF]], [[Xar (archiver)|XAR]], and [[compress|Z]] archives and [[cramfs]], [[Apple Disk Image|DMG]], [[File Allocation Table|FAT]], [[Hierarchical File System (Apple)|HFS]], [[ISO image|ISO]], [[Master boot record|MBR]], [[NTFS]], [[SquashFS]], [[Universal Disk Format|UDF]], and [[Virtual Hard Disk|VHD]] [[disk image]]s. 7-Zip supports the ZIPX format for unpacking only. It has had this support since at least version 9.20, which was released in late 2010. 7-Zip added support for RAR5 in 2015.<ref>[https://www.7-zip.org/history.txt 7-zip.org/history.txt]</ref>
7-Zip can open some [[Windows Installer|MSI]] files, allowing access to the meta-files within along with the main contents. Some Microsoft CAB ([[LZX]] compression) and [[Nullsoft Scriptable Install System|NSIS]] (LZMA) installer formats can be opened. Similarly, some Microsoft executable programs (.[[EXE]]s) that are self-extracting archives or otherwise contain archived content (e.g., some setup files) may be opened as archives.
When compressing ZIP or gzip files, 7-Zip uses its own [[DEFLATE]] encoder, which may achieve higher compression, but at lower speed, than the more common [[zlib]] DEFLATE implementation. The 7-Zip deflate encoder implementation is available separately as part of the AdvanceCOMP suite of tools.
The decompression engine for [[RAR (file format)|RAR]] archives was developed using freely available source code of the unRAR program, which has a licensing restriction against creation of a RAR compressor. 7-Zip v15.06 and later support extraction of files in the RAR5 format.<ref>{{cite web|last1=Pavlov|first1=Igor|title=7-Zip 15.06 beta release notes|url=http://sourceforge.net/p/sevenzip/discussion/45797/thread/c611394e/#1783}}</ref> Some [[backup]] systems use formats supported by archiving programs such as 7-Zip; e.g., some [[Android (operating system)|Android]] backups are in <code>tar</code> format, and can be extracted by archivers such as 7-Zip.<ref>{{cite web|url=https://ajqi.com/how-to-extract-files-from-a-nandroid-backup/|title=How to extract files from a Nandroid Backup|author=Vijay|date=11 May 2013|website=AJQI|access-date=16 April 2017|archive-date=31 March 2017|archive-url=https://web.archive.org/web/20170331134328/http://ajqi.com/how-to-extract-files-from-a-nandroid-backup/|url-status=dead}}</ref>
Some forks add more formats.
==File manager==
7-Zip comes with a file manager along with the standard archiver tools. The file manager has a toolbar with options to create an archive, extract an archive, test an archive to detect errors, copy, move, and delete files, and open a file properties menu exclusive to 7-Zip. The file manager, by default, displays hidden files because it does not follow [[Windows Explorer]]'s policies. The tabs show name, modification time, original and compressed sizes, attributes, and comments ([[4DOS]] <code>[[long filename#descript.ion|descript.ion]]</code> format).
When going up one directory on the root, all drives, removable or internal appear. Going up again shows a list with four options:
* '''Computer''': loads the drives list
* '''Documents''': loads user's documents, usually at <code>%UserProfile%\My Documents</code>
* '''Network''': loads a list of all network clients connected
* '''\\.''': Same as "Computer" except loads the drives in low-level [[filesystem]] access. This results in critical drive files and deleted files still existing on the drive to appear. (NOTE: As of November 2020, access to the active partition in low-level mode is not allowed for currently unknown reasons.)
==Features==
7-Zip supports:
* 32 and 64-bit x86, ARM64 architecture
* File Manager
* Encryption via the 256-bit [[Advanced Encryption Standard|AES]] cipher, which can be enabled for both files and the 7z hierarchy. When the hierarchy is encrypted, users are required to supply a [[password]] to see the filenames contained within the archive. WinZip-developed Zip file AES encryption standard is also available in 7-Zip to encrypt ZIP archives with AES 256-bit, but it does not offer filename encryption as in 7z archives.<ref>{{Cite web|url=https://www.winzip.com/aes_info.htm|title=AES Encryption Information: Encryption Specification AE-1 and AE-2|date=30 January 2009|website=[[WinZip]]}}</ref>
* Volumes of dynamically variable sizes, allowing use for backups on removable media such as writable CDs and DVDs
* Usability as a basic [[orthodox file manager]] when used in dual panel mode
* Multiple-core CPU threading<ref>{{cite web|last1=Atwood|first1=Jeff|title=File Compression in the Multi-Core Era|url=https://blog.codinghorror.com/file-compression-in-the-multi-core-era/|website=Coding Horror|date=28 February 2009 |access-date=4 August 2017}}</ref>
* Opening EXE files as archives, allowing the decompression of data from inside many "Setup" or "Installer" or "Extract" type programs without having to launch them
* Unpacking archives with corrupted filenames, renaming the files as required
* Create [[self-extracting archive|self-extracting single-volume archives]]
* Command-line interface<ref>[https://sevenzip.osdn.jp/chm/cmdline/syntax.htm "Command Line Syntax"]. sevenzip.osdn.jp.</ref>
* Graphical user interface. The Windows version comes with its own GUI; however, ''p7zip'' uses the GUI of the Unix/Linux Archive Manager.<ref>{{cite web|url=https://ubuntuforums.org/archive/index.php/t-782897.html|title=[ubuntu] GUI front end for 7-zip? [Archive] - Ubuntu Forums|website=ubuntuforums.org}}</ref>
* Calculating [[checksum]]s in the formats CRC-32, CRC-64, SHA-1, or SHA-256 for files on disk, available either via command line or Explorer's context menu<ref name="7zipHistory" />
* Available in 89 languages
* Ability to optionally record creation dates (<code>tc</code>) and last access dates (<code>ta</code>) in archives (in addition to modification dates).<ref>[http://sevenzip.osdn.jp:80/chm/cmdline/switches/method.htm -m (Set compression Method) switch]</ref>
==Versions==
Two [[Command-line interface|command-line]] versions are provided: 7z (7z.exe), using external libraries; and 7za (7za.exe), which is a standalone executable containing built-in modules, but with compression/decompression support limited to [[7z]], [[ZIP (file format)|ZIP]], [[gzip]], [[bzip2]], [[compress|Z]] and [[tar (file format)|tar]] formats. A 64-bit version is available, with support for large memory maps, leading to faster compression. All versions support multi-threading.
=== Forks ===
* ''p7zip'' is a fork for [[Unix-like]] operating systems (including [[Linux]], [[FreeBSD]], and [[macOS]]), [[FreeDOS]], [[OpenVMS]], [[AmigaOS 4]], and [[MorphOS]]. It offers the 7za version only.<ref name="p7ziphome" />
* 7-zip ZS is a fork with [[Zstandard]] and various other compression algorithms added to the file format.<ref>{{cite web |title=Milkys Homepage - 7-Zip with support for Zstandard, Brotli, Lz4, Lz5 and Lizard Compression |url=https://mcmilk.de/projects/7-Zip-zstd/ |website=mcmilk.de}}</ref>
** ''p7zip-zstd'' (p7zip with zstd) is p7zip with ZS additions.<ref>{{cite web |title=p7zip-zstd |url=https://github.com/p7zip-project/p7zip |publisher=p7zip-project |date=4 May 2023}}</ref>
* ''NanaZip'' is a fork integrating changes from many sources, modernized for the [[Microsoft Store]].<ref>{{cite web |title=NanaZip: The 7-Zip derivative intended for the modern Windows experience |url=https://github.com/M2Team/NanaZip |publisher=M2-Team |date=6 May 2023}}</ref>
=== Plugins ===
7-zip comes with a plug-in system for expansion. The official "Links" page points to many plugins written by TC4Shell, providing extra file support.<ref>{{cite web |title=Links |url=https://7-zip.org/links.html |website=7-zip.org}}</ref>
==Software development kit==
7-Zip has a [[LZMA]] [[Software development kit|SDK]] which was originally [[Dual licensing|dual-licensed]] under both the [[GNU Lesser General Public License|GNU LGPL]] and [[Common Public License]],<ref>{{cite web | url = http://sourceforge.net/projects/sevenzip/files/LZMA%20SDK/4.23/ | title = Browse /LZMA SDK/4.23 | access-date = 2014-02-12 | publisher = [[SourceForge]]}}</ref> with an additional special exception for linked binaries. On 2 December 2008, the SDK was [[Software relicensing|placed]] by Igor Pavlov in the [[public domain]].<ref name="LZMA_SDK">{{cite web|url=https://www.7-zip.org/sdk.html|title=LZMA SDK (Software Development Kit)|last=Pavlov|first=Igor|year=2013|access-date=16 June 2013}}</ref>
==Security==
On older versions, self-extracting archives were vulnerable to [[arbitrary code execution]] through [[DLL hijacking]]: they load and run a DLL named UXTheme.dll, if it is in the same folder as the executable file.<ref>{{cite web|last1=Kanthak|first1=Stefan|title=Executable installers are vulnerable^WEVIL (case 7): 7z*.exe allows remote code execution with escalation of privilege|url=http://seclists.org/fulldisclosure/2015/Dec/34|website=SecLists.org|date=8 December 2015}}</ref><ref>{{cite web|last1=Kanthak|first1=Stefan|title=Executable installers are vulnerable^WEVIL (case 14): Rapid7's ScanNowUPnP.exe allows arbitrary (remote) code execution|url=http://seclists.org/fulldisclosure/2015/Dec/90|website=SecLists.org|date=22 December 2015}}</ref><ref>{{cite web|last1=Hart|first1=Jon|title=ScanNow DLL Search Order Hijacking Vulnerability and Deprecation|url=https://community.rapid7.com/community/infosec/blog/2015/12/21/scannow-dll-search-order-hijacking-vulnerability-and-deprecation|website=Rapid7.com|date=21 December 2015}}</ref> 7-Zip 16.03 Release notes say that the installer and SFX modules have added protection against DLL preloading attack.<ref name="7zipHistory" />
Versions of 7-Zip prior to 18.05 contain an [[arbitrary code execution]] vulnerability in the module for extracting files from [[RAR (file format)|RAR archives]] ({{CVE|2018-10115}}), a vulnerability that was fixed on 30 April 2018.<ref>{{cite web|url=https://www.cisecurity.org/advisory/a-vulnerability-in-7-zip-could-allow-for-arbitrary-code-execution_2018-049/|title=A Vulnerability in 7-Zip Could Allow for Arbitrary Code Execution|website=cisecurity.org|date=2018-05-01}}</ref>
Versions prior to 23.0 also contained an [[arbitrary code execution]] vulnerability, fixed on 7 May 2023.<ref>{{cite web|url=https://www.zerodayinitiative.com/advisories/ZDI-23-1165|title=7-Zip 7Z File Parsing Integer Underflow Remote Code Execution Vulnerability|website=zerodayinitiative.com|date=2022-08-23}}</ref> A year later, a severe [[Remote code execution]] vulnerability was found on versions prior to 24.07 ({{CVE|2024-11477}}), it was fixed on 20 November 2024.<ref>{{cite web |title=7-Zip RCE Vulnerability Let Attackers Execute Remote Code |url=https://gbhackers.com/7-zip-vulnerability/ |website=GBHackers Security {{!}} #1 Globally Trusted Cyber Security News Platform |access-date=26 November 2024 |date=25 November 2024}}</ref>
==Reception and usage==
Snapfiles.com in 2012 rated 7-Zip 4.5 stars out of 5, noting, "[its] interface and additional features are fairly basic, but the compression ratio is outstanding".<ref>{{cite web|title=7-Zip file compression tool |publisher=WebAttack |work=Snapfiles.com |url=http://www.snapfiles.com/get/7zip.html |access-date=2012-10-12}}</ref>
On [[TechRepublic]] in 2009, Justin James found the detailed settings for [[File Manager (Windows)|Windows File Manager]] integration were "appreciated" and called the compression-decompression benchmark utility "neat". And though the archive dialog has settings that "will confound most users", he concluded: "7-Zip fits a nice niche in between the built-in Windows capabilities and the features of the paid products, and it is able to handle a large variety of file formats in the process."<ref>{{cite web|url=https://www.techrepublic.com/blog/product-spotlight/review-7-zip-file-compression-application/|title=Review: 7-Zip file compression application|last=James|first=Justin|date=10 November 2009|website=[[TechRepublic]]|pages=1–2}}</ref>
Between 2002 and 2024, 7-Zip was downloaded 428 million times from [[SourceForge]] alone.<ref>[https://sourceforge.net/projects/sevenzip/files/stats/timeline?dates=2001-07-20+to+2024-02-01 7-zip file download stats] on [[SourceForge.net]] (February 2024)</ref>
The software has received awards, In 2007, SourceForge granted it community choice awards for "Technical Design" and for "Best Project".<ref name="7zipAward2007">{{cite web|url=https://sourceforge.net/blog/cca07/|title=SourceForge.net: 2007 Community Choice Awards|date=15 June 2007|website=[[SourceForge]]|archive-url=https://web.archive.org/web/20100326163008/http://sourceforge.net/blog/cca07/|archive-date=26 March 2010|url-status=live|access-date=16 April 2010}}</ref> In 2013, [[Tom's Hardware]] conducted a compression speed test comparing 7-ZIP, MagicRAR, [[WinRAR]], WinZip; they concluded that 7-ZIP beat out all the others with regards to compression speed, ratio, and size and awarded the software the 2013 Tom's Hardware Elite award.<ref>{{Cite web|last1=Masiero|first1=Manuel|last2=Roos|first2=Achim|date=19 March 2013|title=Compression Performance: 7-Zip, MagicRAR, WinRAR, WinZip|url=https://www.tomshardware.com/reviews/winrar-winzip-7-zip-magicrar,3436.html|access-date=2021-04-25|website=[[Tom's Hardware]]|language=en}}</ref>
==See also==
{{Portal|Free and open-source software}}
* [[7z]]
* [[Comparison of archive formats]]
* [[Comparison of file archivers]]
* [[List of archive formats]]
==References==
{{Reflist}}
==External links==
{{Commons category}}
* {{SourceForge|sevenzip|7-Zip}}
* [https://portableapps.com/apps/utilities/7-zip_portable 7-Zip Portable] at [[PortableApps.com]]
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{{Compression software}}
{{FOSS}}
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