I’ve posted numerous articles (http://best-mac-tips.com/?s=rar+files) on extracting and repairing RAR files using the OS X Terminal. Of course, hacking around in Terminal is not everyone’s cup of tea. There are plenty of applications, both free and commercial, for handling archive formats such as RAR on Mac. Here’s a couple I recommend:
This is one I use a lot, and have had no issues with. It is completely free, and supports many archive formats ( Zip, Tar-GZip, Tar-BZip2, RAR, 7-zip, LhA, StuffIt and many other old and obscure formats most of us have likely never heard of). You can read a bit about it on the developer’s web site, although the app itself is install from the Mac App Store, here. There’s not much to show for screenshots except the preference panel. You see, The Unarchiver is unobtrusive and doesn’t require a user interface. Just double click your rar file and The Unarchiver will go to work extracting it. As simple as that.
This open source app has versions for Mac, Windows, Linux, and Android. It provides a long list of features for both unarchiving (expanding) and archiving (compressing) files. It supports the RAR format, and many others. It provides strong 256-bit AES encryption for creating highly secure archives. You can check it out here. Here’s a nice screenshot: