How to convert MP3 to M4B
- Add your .MP3 file - drop it in the box above or click to browse.
- Convert it to .M4B in a few seconds.
- Download your new .M4B file.
What to expect
- M4B stores AAC audio, so converting from MP3 is a second lossy encode.
- The bookmarking and resume behavior comes from the container; a source MP3 provides no chapter data on its own.
- The result is standard (non-DRM) audio; it will not carry FairPlay protection from any store files.
Frequently asked questions
What does converting MP3 to M4B add?
M4B is an MPEG-4 audiobook file that supports chapter markers and remembers your playback position. Converting MP3 to M4B repackages the audio as AAC in that container so it behaves as an audiobook.
Does the audio quality change?
M4B holds AAC audio, so this is a lossy-to-lossy re-encode from the MP3. The result is close to the source but does not improve on it, since the MP3 was already compressed.
Where does an M4B file open?
On Mac or iPhone, Apple Books opens M4B with chapter navigation. On Windows it plays in iTunes or players like VLC.
Will chapter markers appear automatically?
Chapter and bookmarking support is a feature of the M4B container, but a plain MP3 has no chapter data to carry over, so the output will not contain chapters unless they are added separately.
Programs that convert MP3: MediaMonkey · AVS Audio Converter · Helium Music Manager · AudioBook Binder · Tiny Audio Converter
