How to open .rar files on a Mac

Double-click a .rar file on a Mac and nothing useful happens. macOS ships with Archive Utility, which handles .zip, .tar, .gz and a few relatives — but not RAR. RAR is a proprietary format owned by RARLAB, and Apple has never licensed a decoder for it.

The usual advice is to install something. For most RARs you do not need to.

Open it in your browser, without uploading it

Drop the .rar into the file.zip inspector. It lists every entry with its size, and extracting gathers the whole archive into a ZIP in one pass, which your browser downloads — then macOS opens that ZIP natively.

The important part is the part most “open RAR online” sites get wrong: nothing is uploaded. The decoder is a WebAssembly build of libarchive that runs inside the browser tab, reading the file straight off your disk. Your archive is not sent to a server, not held in a queue, and not stored anywhere awaiting deletion — because it never left the machine in the first place.

Two things to know before you rely on it:

• It extracts the whole archive, not single files. RAR is decoded in order rather than indexed, so one file cannot be unpacked on its own the way it can from a ZIP.
• The archive has to be under 500 MB. Unlike ZIP and tar, RAR cannot be read as a stream — it is loaded into memory whole — so the page refuses anything larger rather than exhausting the tab.

Within those limits there is nothing to install, nothing to keep updated, and no permissions to grant. For a one-off .rar someone emailed you, this is the whole job.

The same drop also answers a question worth asking before you install anything.

It might not be a RAR at all

A file extension is a label someone typed. It is not the file. Archives get renamed by download managers, by email clients, by well-meaning people zipping up a folder of RARs and calling the result photos.rar.

Every archive format announces itself in its opening bytes. A real RAR starts with the ASCII characters Rar!. A ZIP starts with PK. A 7-Zip archive starts with 7z. Those bytes are the truth; the extension is a guess.

This matters because “I can’t open this RAR” turns out, often enough, to mean “this isn’t a RAR.” The inspector reads those leading bytes and opens the file as whatever it actually is — so if your .rar is really a ZIP, or your .zip is really a RAR, it simply works, and you find out why.

When you need a desktop app

Install one of these if you want .rar files to open from Finder by double-clicking, or if you hit one of the cases below — a password-protected archive, a multi-part set, or anything over 500 MB.

The Unarchiver is the usual answer — free, from the App Store, and it registers itself as the handler for .rar so double-clicking starts working. It reads RAR alongside a long list of other formats.

Keka is the other well-regarded free option, and it can create archives as well as extract them. If you also want to make .7z files, it is the better pick.

unar on the command line comes from the same project as The Unarchiver and is available through Homebrew:

brew install unar
unar archive.rar

Worth knowing if you are extracting many files at once, or working over SSH.

The multi-part case

If you have archive.part1.rar, archive.part2.rar and so on, do not try to extract each one. They are pieces of a single archive, and no individual part holds a complete copy of anything — a split can fall in the middle of a file.

This is a job for a desktop app: file.zip reads one file at a time and does not join volumes. Put every part in the same folder and open part 1 only; the extractor finds the rest by name. If any part is missing, extraction fails partway through, and there is no way to reconstruct the missing content from the parts you do have. No tool changes that — the bytes are simply not there.

What about password-protected RARs?

A desktop extractor will prompt you for the password, and that works fine. file.zip cannot decrypt RAR. It will still list the archive — encrypted entries leave their names and sizes readable — but the contents stay closed, and no password will open them here, because the libarchive build the page uses has no RAR decryption compiled in. The page says so when it sees one. Use The Unarchiver, Keka or WinRAR for those.

What no tool can do is recover a password you do not have. RAR encrypts the file contents with AES, and there is no back door — the “RAR password recovery” products you will find advertised are brute-force guessers, and against a decent password they will not finish in your lifetime. If you did not set the password and cannot ask whoever did, the archive is not openable, by any tool, at any price.

Which one should you use?

The short rule: if your .rar is a plain one — not encrypted, not split into parts, under 500 MB — open it in the browser. That covers most of them, it is faster than installing anything, and the file stays on your Mac.

Install The Unarchiver or Keka for everything else: Finder integration, passwords, multi-part sets, and the genuinely large archives. The two are not in competition — the browser handles the file you have today, and the desktop app is there for the ones it cannot.