You have an audiobook, but it's an .M4B file that only seems to work inside iTunes or Apple Books. You can't load it into your favourite podcast app, it won't play in the car, and your Android phone doesn't know what to do with it. M4B is Apple's audiobook format — and converting it to MP3 frees the book to play on virtually anything.
What is an M4B file?
M4B is an MPEG-4 audio file, the same family as M4A, but designated for audiobooks. It supports chapter markers and remembering your place, which is why Apple uses it. The catch is that support outside the Apple ecosystem is patchy, so on most other players and apps the file simply won't open.
MP3, by contrast, plays on every phone, car stereo, smart speaker, and MP3 player ever made — so converting is the simplest way to take your audiobook with you.
How to convert M4B to MP3
Open the M4B to MP3 converter, upload your audiobook file, choose MP3, and download. The full audio is preserved. Because audiobooks are long, the file can be large — see the note below on size limits.
What happens to chapters?
MP3 does not carry M4B's chapter markers, so the result is one continuous audio file. Many audiobook and podcast apps still let you bookmark and resume MP3s, and you can split a long book into parts if you prefer smaller files to move between devices.
Why convert your audiobook
Play anywhere
Any phone, car, speaker, or MP3 player — no Apple device required.
Use any app
Load books into the podcast or audiobook app you actually like.
Back it up
MP3 is the most durable, universally-supported format for archiving a library.
A note on DRM
This converts standard, DRM-free M4B files — for example audiobooks you created or downloaded without copy protection. Audiobooks with DRM (some store purchases) are encrypted and cannot be converted. Always convert only content you own and are allowed to format-shift.
The bottom line
M4B keeps audiobooks tied to Apple; MP3 sets them free. Convert to MP3 to listen on any device or app, and split long books into parts if that suits your listening. Keep the original M4B if you want to preserve chapter markers for Apple playback.
Convert your audiobook
Free online M4B to MP3 converter. Take your audiobooks anywhere — no iTunes, no watermark.
