.M4A File Extension

MPEG-4 is a multimedia container format that supports video, audio, subtitle, and image data encoded in different codecs. MPEG-4 files that store video bear the .mp4 file extension ( .MP4 files). However, if the MPEG-4 file only stores audio, it is saved with the .m4a extension, which stands for "MPEG-4 Audio." This name change helped distinguish between MPEG-4 video files and MPEG-4 audio-only files.

You will most likely encounter M4A files when downloading audio content via the Apple iTunes Store. The content, typically songs, is encoded with AAC compression, which significantly reduces the size of each file. In addition, songs that include copyright protection have an .m4p file extension ( .M4P files).

To open a .m4a file, you need compatible software that supports this file format.