What is the difference between M4A and AAC Audio Files?

audio ffmpeg aac m4a
alexandertr picture alexandertr · Aug 7, 2013 · Viewed 77.6k times · Source

Is there any difference between M4A audio files and AAC audio files or are they exactly the same thing but with a different file extension?

Answer

Roman R. picture Roman R. · Aug 7, 2013

.M4A files typically contain audio only and are formatted as MPEG-4 Part 14 files (.MP4 container).

.AAC is not a container format and instead it is a raw MPEG-4 Part 3 bitstream with audio stream encoded.

Note that M4A does not have to contain exactly AAC audio, there are other valid options as well.

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