The difference between rar and RAR5 compression


What is the difference between rar and RAR5 compression ?
Which is better for which purpose vs the compression time.

Best Answer

When you're choosing a compression type in WinRAR, "RAR" uses v2.9 (sometimes referred to as v4) of the algotrithm, where selecting "RAR5" uses v5. Both are detailed in the wiki article, which others have already linked to.

RAR5 supports some additional encryption features, but you're asking which one is better for compression - from the wiki, it looks like RAR5 might by trivially better for compression speed and smaller in some very specific cases, but the advantages appear to be all on the side of the viewer/decompressor:

  • Improved damaged archive recovery
  • Improved file table (meaning quicker browsing of an archive)
  • Multicore decompression support

In exchange, you're taking the chance that the end user won't have a program that supports the new format, and won't be able to decompress your archive. However, if you're keeping the archive for yourself or you're sending it to somebody that you know has a program that can view it, it looks like RAR5 is the better format.