ZIP vs RAR vs 7z: Which Archive Format Should You Use?

ZIP is the oldest of the three. Phil Katz released PKZIP through his company PKWARE in 1989 and published the format description, a text file called APPNOTE.TXT, so anyone could write a compatible program. Its main compression method, Deflate, arrived with PKZIP 2.0 in 1993 and is the same algorithm inside PNG images and gzip. Because the specification was free to implement, ZIP readers ended up everywhere: in Windows, in macOS, in phones, in Java (JAR files) and in Office documents, which are ZIP archives with a different extension.

RAR came next. Eugene Roshal released it in 1993, and his brother Alexander manages RARLAB, which sells WinRAR. The format is proprietary. Extracting is free, and RARLAB publishes UnRAR source code that other programs may use to read archives, but its license forbids using that code to build a RAR creator. That is why you can open a .rar in dozens of apps, yet creating one almost always means WinRAR or its command-line sibling. In exchange you get two features the others lack in the same form: solid archives by default and recovery records.

7z is the youngest. Igor Pavlov released 7-Zip in 1999 along with the 7z format and its LZMA compression, later joined by LZMA2, which splits work across processor cores. 7-Zip is free and open source under the LGPL, and the format is documented, so tools such as Keka on the Mac and p7zip on Linux write it too. You can download the program from 7-zip.org. Pavlov still maintains it, and new versions appear several times a year. Its own file manager is plain, but the format is what matters: almost every third-party archiver on Windows, Mac and Linux can read 7z today.

How much an archive shrinks depends far more on what goes in than on the format. Plain text, CSV exports, logs, source code and old .doc files are full of repetition, and all three formats compress them well: a folder like that typically ends up at a third or less of its original size in ZIP, and 7z with LZMA2 usually cuts another 10–30% on top. RAR typically lands between the two. The gap widens when a folder holds many similar small files, because 7z and RAR can pack them as one continuous stream, a solid archive, while ZIP compresses each file separately and cannot reuse what it learned from the previous one.

Photos, videos and music behave differently. JPG, HEIC, MP4, MP3 and most PDFs are already compressed, so any archive format saves only a percent or two on them, sometimes nothing at all. Modern Office files (.docx, .xlsx, .pptx) are ZIP archives internally and barely shrink either. If you zip a 2 GB folder of holiday videos expecting a 1 GB file, you will be disappointed whichever format you pick. The archive is still useful for bundling hundreds of files into one download, just not for making them smaller. Compress those files first if size is the goal, then archive the results.

Speed runs the other way. Deflate in ZIP is fast to create and very fast to extract, even on an old laptop or phone. 7z at its Ultra level can take several times longer to create and needs much more memory, though extraction stays reasonably quick. RAR sits in the middle. For a one-off email attachment, the extra minutes 7z spends rarely pay off; for a backup that will sit on a drive for years, a 20% smaller file is worth waiting for. Most tools also offer a Store or Fast level that skips heavy compression, the sensible choice for media.

All three formats can carry a password, but they do not protect the same things. The original ZIP encryption, usually called ZipCrypto, dates from the early 1990s and was shown to be breakable with a known-plaintext attack published in 1994; free tools still exploit it today. ZIP can also use AES-256, an extension WinZip introduced in 2003 that 7-Zip, WinRAR and current built-in unzip tools read. RAR5 uses AES-256 as well, and so does 7z. With a long, random password, any of those three is effectively unbreakable by guessing.

The difference is what stays visible. A ZIP shows its list of file names, sizes and dates to anyone, even when the contents are encrypted. 7z can encrypt the header too, so nothing is listed until the password is entered, and RAR offers a similar option labelled Encrypt file names in WinRAR. If a file name such as 2025-tax-return-SSN.pdf is itself sensitive, that matters. The same thinking applies to single documents: a password on the file itself, as described in our guide on how to password protect a PDF, can be simpler than wrapping one file in an archive.

Garbled file names are a ZIP problem with a long history. Early ZIP tools stored names in whatever character set the computer used, such as the old DOS code page in the US or Shift-JIS in Japan, without recording which one. The specification added a flag for UTF-8 names in 2006, but plenty of tools ignored it for years. The result is familiar to anyone who has received a ZIP from another country: Korean, Cyrillic or accented names turn into strings of symbols after extraction. 7z and RAR5 store names in Unicode from the start, so they rarely have this issue. If you send ZIPs abroad, create them with a current tool that writes UTF-8 names.

Size limits used to matter too. The original ZIP format capped each file and the whole archive at 4 GB and allowed at most 65,535 entries. ZIP64, added in 2001, removed those ceilings, and every current unzip app reads it, although a few very old programs and some embedded devices do not. 7z and RAR were designed with large files in mind and have limits far beyond any drive you own, so a 50 GB disk image is not a problem for either. If an archive tool or device reports a broken ZIP over 4 GB, a missing ZIP64 reader is the usual cause, and a current version of 7-Zip or the system extractor fixes it.

All three can split one archive into parts of a fixed size, which helps with upload caps and old FAT32 drives that reject files over 4 GB. The naming differs: ZIP uses .z01, .z02 and a final .zip; RAR5 uses .part1.rar, .part2.rar; 7z uses .7z.001, .7z.002. The rule is the same for all of them: you need every part in one folder to extract anything, and a missing part breaks every file that spans it. Split parts also add risk, so check that each one downloaded completely before you delete anything.

Built-in support has changed more in the last three years than in the twenty before. Windows 11 version 23H2, released in late 2023, added extraction of RAR, 7z, TAR and several other formats to File Explorer using the open-source libarchive library, and version 24H2 added Compress to options for 7z and TAR alongside ZIP. No version of Windows creates RAR. Windows 10 still handles ZIP only. Apple has not followed: Archive Utility on macOS opens ZIP (plus gzip and tar) but not RAR or 7z, so Mac users install The Unarchiver or Keka.

Phones stay with ZIP. The iPhone Files app has opened ZIP since iOS 13 and can compress files into one, and Files by Google on Android extracts ZIP. RAR and 7z on a phone need a third-party app, which is exactly the step most recipients will not take. If you are unsure what the other person has, the step-by-step guide to unzipping files on any device shows what each system offers. Work and school computers add another layer, since many block app installs, so a ZIP is often the only archive such a machine can open at all.

The format choice is really a question about the person on the other end. When you send files to a client, a teacher, a relative or an upload portal, ZIP is the only option you can count on, and the few percent you might save with 7z are not worth a confused reply. You can create a ZIP online by picking ZIP in Archive format and, for anything private, setting a Password with Encryption on AES-256 under Advanced settings. When the archive is only for you, the calculation flips: 7z gives smaller backups, header encryption and a free tool on every desktop system.

Email adds its own rules. Gmail limits attachments to 25 MB and Outlook.com to 20 MB, and zipping videos will not get you under those limits because they barely compress. Gmail also blocks executable files such as .exe and .bat even inside a ZIP or other archive, and it refuses some password-protected archives because it cannot scan them. For large sets, use Split into parts of to make pieces below the limit, or share a cloud link instead. When the recipient asks for a single file, a ZIP of a few large documents is still easier to handle than ten separate attachments.

Converting an archive means extracting every file and packing the same files again, so the contents come out byte for byte identical. The most common direction is toward ZIP: you received a RAR or 7z, and you want something a colleague can open without installing anything. You can repack a RAR as a ZIP or turn a 7z into a ZIP in the browser; if the source has a password, it goes in Current password, and a New password locks the ZIP again. Expect the ZIP to be larger when the archive held lots of text, because solid compression does not carry over.

Other properties belong to the container and disappear with it. Header encryption from 7z or RAR does not survive, because ZIP always lists file names. Unix permissions from a TAR.GZ may be dropped. And RAR's recovery record, which WinRAR can use to rebuild a damaged archive, is not part of ZIP or 7z at all. None of this changes the files themselves; it only changes how they are stored and protected.

Going the other way, from ZIP to 7z, makes sense for archiving, and creating a RAR requires WinRAR from rarlab.com. If you just need the files out of an archive rather than a new one, extract it online instead of converting, and skip a step entirely.

Find your situation in the left column. When two rows apply, the one about the recipient wins, because an archive nobody can open is worth less than one that is 20% bigger. Every row assumes current tools at both ends; if the recipient uses an old work laptop or a locked-down school computer, lean toward plain ZIP even more.