Turn M4B audiobooks into MP3. It is converted in your browser, so the file never leaves your device.
Drop M4B files here
or choose from your computer paste with Ctrl V
from Photos or Files
Ready · other file types work too0 bytes uploaded, ever
Drop M4B files onto the box above, or click it to choose them. ToAny reads the file's contents to detect the type, so a wrong extension does not matter.
Press Convert. Open Options first if you want to change the defaults. The work happens in this tab.
Save the MP3, or download everything as one ZIP if you converted several files.
The M4B to MP3 converter is part of this page and runs inside your browser. Your audiobooks are never sent to ToAny or to anyone else.
Nothing has to travel to a server and back, so the conversion starts the moment you press Convert, even on a slow connection.
No sign-up, no email address and no watermark. Add several files and download them together as a ZIP.
M4B only shows chapters and bookmarks in apps that treat it as an audiobook. MP3 plays on every phone, computer, car stereo and speaker. An M4B file usually holds AAC with chapters. M4B is at home in audiobooks with chapters and a remembered playback position; MP3 is the usual choice for music and podcasts that must play anywhere. Both formats are lossy, so the content is compressed a second time; start from the best copy you have.
The defaults suit most files. Under Options you can choose the bitrate and trim the start and end.
The conversion uses your browser's own video and audio codecs (WebCodecs), with hardware acceleration where the device has it; the file is read from disk as it goes and can be up to 2 GB. Where the browser lacks a codec, the page falls back to the compatibility engine. MP3 is written at 192 kbps unless you choose another bitrate.
M4B is an M4A file with a different extension, marking it as an audiobook so that players offer chapters, bookmarks and a remembered position. Inside it is ordinary AAC audio. Podcasts and audiobooks are commonly sold or shared as M4B.
Opens in Apple Books, iTunes and Music, VLC and most audiobook apps
M4B converterMP3 is the audio format everything plays. It shrinks audio to roughly a tenth of its uncompressed size by discarding sound most listeners cannot hear. Newer codecs are more efficient, but nothing matches its compatibility.
Opens in Every phone, computer, car stereo and speaker
MP3 converter| M4BAudiobook | MP3MP3 audio | |
|---|---|---|
| Stands for | MPEG-4 audiobook | MPEG-1 Audio Layer III |
| Type | Audio | Audio |
| Compression | Lossy (AAC) | Lossy |
| Introduced | The 2000s, by Apple | 1993, by the Fraunhofer Society and the Moving Picture Experts Group |
| Opens in | Apple Books, iTunes and Music, VLC and most audiobook apps | Every phone, computer, car stereo and speaker |
| Best for | Audiobooks with chapters and a remembered playback position | Music and podcasts that must play anywhere |
| File extension | .m4b | .mp3 |
No. The M4B to MP3 conversion runs inside your browser, on your own phone or computer. The file is not sent to ToAny or to anyone else.
MP3 is a lossy format, so a small amount of detail is traded for a smaller file. At the default setting the difference is hard to notice. You can choose the bitrate under Options.
Yes. Add as many as you like, convert them together and download each result or all of them as one ZIP.
The steps are the same everywhere because ToAny runs in the web browser: open this page in a current version of Chrome, Edge, Safari or Firefox, add the M4B file, press Convert and save the MP3. There is nothing to install.
Yes. Files up to 2 GB are accepted. Beyond that the limit is your device's memory, since nothing is uploaded; a computer copes with large files better than a phone.