Hello there! I'm looking for a free program that can convert any or most music formats (FLAC, Ogg Vorbis, MP4, etc.) into 320-quality MP3 (48000 HZ). I've done online searches, and there are way too many to choose from; plus, I have no sure way of finding out about their reliability (or lack thereof) until I actually install and use them. By reliability I mean that the program has to do what I want it to do, namely convert as many music formats as possible into high-quality MP3; plus, it would be nice if I could install it without opening up my computer to viruses and other malware. If anybody out there has any suggestions, I'm all ears.

http://www.online-convert.com/

Free.

Foobar2000 (http://www.cnet.com/how-to/how-to-convert-flac-audio-files-to-mp3-with-foobar2000/), accept no substitutes.

Converts everything to everything, single files or batches of them, highly customizable, etc, etc, if i continue to praise all the aspects
of this program we'll still be here tomorrow, i've been using it for 3 Years without a single complaint. 100 % free of course.

If you're on Mac, xAct (http://xact.scottcbrown.org/) is one of the best solutions I've come across.

Foobar2000 (http://www.cnet.com/how-to/how-to-convert-flac-audio-files-to-mp3-with-foobar2000/), accept no substitutes.

:this: For Windows.
You didn't specify what OS you are using.

Constant development. No fees for upgrades.
And an active community with a lot of questions already asked and solutions presented (if you search the HydrogrenAudio forums).
They're also going to be releasingn a Mobile version of FB2K in the future: Android, iOS, Windows, etc.
That will probably be paid software, however. Maybe free with in-app purchases.

Once you set it up, you only have to set it up once.
After that, everything becomes easier for future operations.

I, on the other hand, use batch scripts to do my bidding.

MAC: a lot of people say xAct as emj point out.

Yeah, Foobar is a fantastic program. Super-fast conversion too.

Redacted

Yes, Xact on mac does the job!

For Windows I suggest LameXP (http://lamexp.sourceforge.net/) or if you want a veritable Swiss army knife of programs get the Free Audio Video Pack (http://www.pazera-software.com/products/free-audio-video-pack/), it's the best free software suite that I have ever used in 15 years.