How to convert M4B to M4A
- Add your .M4B file - drop it in the box above or click to browse.
- Convert it to .M4A in a few seconds.
- Download your new .M4A file.
What to expect
- No audio quality is lost - the AAC data inside
.m4band.m4ais identical; this is a container relabel, not a re-encode. - Chapter markers and bookmarks may not appear in general music players after renaming, though dedicated audiobook apps such as Apple Books or BookPlayer often still read them.
- DRM-protected M4B files from the iTunes Store cannot be converted this way - they require an authorised Apple device regardless of extension.
Frequently asked questions
Does renaming `.m4b` to `.m4a` reduce audio quality?
No - both formats use the same AAC codec in the same MP4 container; only the extension and an internal brand marker differ, so the audio is byte-for-byte identical.
Will chapters appear after I rename the file?
Most music players ignore the chapter track in an
.m4a because they do not expect it; dedicated audiobook apps such as Apple Books or BookPlayer are more likely to display them.Can I convert a DRM-protected M4B?
No - FairPlay-protected M4B files bought from the iTunes Store require an authorised Apple device to play regardless of the file extension.
When should I use `ffmpeg` instead of just renaming?
Renaming works for a single file;
ffmpeg is more useful for batch processing or when a player is strict about the internal container header rather than the extension alone.
