Audio File Convert exports to 20 audio file formats and a multitude of codecs, all of which are shown with the
The original formats for storing audio files were all uncompressed because these are easy to work with, and can be played by even very early CPUs. However, uncompressed audio files are very large, easily going up to 10 MB/minute. These formats all share similar codec options like
BEF64. Smaller numbers give smaller files, but larger numbers give higher quality. If you're not sure what to choose, go with
Not every codec is supported by every file format, but you can use this as a guide to get started choosing your codec. Once you've chosen a codec, you can look at the output of
afconvert -hf to pick a suitable container file format.
(Note: I have excluded the MPG formats such as MPG3/MP3 from this list because they just do not work.)
Once you've chosen a file format and codec, you run afconvert like this:
afconvert -f FORMAT -d CODEC SOURCEFILE [-o DESTINATIONFILE]
It is necessary to specify both the file format and the codec, otherwise an error is shown. If you omit the
-o option, afconvert will pick a name and extension based on the other inputs.
If you have an audio file called
MyAudio.m4a you could try these commands.
afconvert -f AIFF -d BEI32 MyAudio.m4a -o MyAudio.aiff
afconvert -f WAVE -d LEI32 MyAudio.m4a -o MyAudio.wav
# Apple Lossless
afconvert -f m4af -d alac MyAudio.m4a -o MyAudio.m4a
afconvert -f flac -d flac MyAudio.m4a -o MyAudio.flac
afconvert -f mp4f -d aac MyAudio.m4a -o MyAudio.mp4