If you’re an experienced computer user then you probably don’t spend much time thinking about archive formats. You’ve just installed something like 7-Zip and are ready to extract whatever you find.
Not everyone is as well equipped, though, so if you’re sharing something like a .gz with others then it might be wise to convert it to a more basic .zip, first.
If you can’t do this easily with your regular archiving tool then you might be interested in ArcConvert, an open source application for directly converting individual archives between various formats.
The program can read these formats: ZIP/ LZH / CAB / ZIP / ARJ / ACE / RAR / TAR / TGZ / GZ / Z / BZ2 / YZ1 / YZ2 / GCA / BEL / RPM / DEB/ BH / Noa32 / HKI / PAQAR / SQX /HA /ZOO /UHARC /LFB / ZLIB / UCL / IMP / RS / SPL / APK / Arc / DZ / MSI / ALZ / PMA / PAQ7 / CHM / UDA / PAQ8 / Cryptonite / ISO / LZOP / BMA / ZIP AES (128/192/256) / Nanozip Alpha/ XZ/ FreeArc/Zpaq/GZA.
ArcConvert can export to ZIP, 7-ZIP, CAB, LHA, TAR, TGZ, BZ2, YZ1, BGA, RAR, ACE, NOA32, PAQAR, UHARC, YZ2, DZ, HA, XZ, FreeArc, or ARJ/PAQ9/GZA, although beware, RAR and ACE support isn’t native: you’ll need WinRar and WinAce installed.
Basic conversion works as you’d expect. Choose a file (only one file, unfortunately -- no batch processing here), an export format, click Convert and the new archive is created for you.
There are some extras, too. The program can validate an archive with a click; preserve the original file date/ time; run at a custom process priority.
It also compares the original and converted archive file sizes. If the new file is larger, you’ll be asked if you want to try again with another format; if it’s smaller, you’ll be asked if you’d like to delete the original.
The lack of batch processing is a problem, and the interface looks and feels like it was thrown together in 30 seconds (and never checked again). But if you just need an easy way to convert single archives between a host of file types then ArcConvert will get the job done.