Convert M4B audiobooks,
free in your browser.

No uploads. No accounts. No limits.
Every conversion runs entirely on your device.

Drop your audio file here
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M4B · MP3 · M4A

All converters

M4B → MP3
Split audiobook chapters into individual MP3 tracks
M4B → M4A
Lossless instant copy, Apple and Android compatible
MP3 → M4B
Merge multiple MP3 files into a single M4B audiobook
M4A → M4B
Convert M4A audio files to M4B audiobook format

From the articles

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Guides on converting audiobooks
How M4B, MP3, and M4A actually differ — and the right way to convert between them.