Turn M4B audiobooks into M4A. 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 M4A, or download everything as one ZIP if you converted several files.
The M4B to M4A 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. M4A sounds better than MP3 at the same file size and is native to Apple devices. An M4B file usually holds AAC with chapters. M4B is at home in audiobooks with chapters and a remembered playback position; M4A is the usual choice for music and voice memos on Apple devices. 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. M4A 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 converterM4A is an MP4 file that contains only audio, usually AAC. iPhone Voice Memos and the iTunes Store use it. It sounds better than MP3 at the same size but is not accepted everywhere MP3 is.
Opens in Apple devices, Android, current browsers; some car stereos and older players do not
M4A converter| M4BAudiobook | M4AM4A audio | |
|---|---|---|
| Stands for | MPEG-4 audiobook | MPEG-4 Audio |
| Type | Audio | Audio |
| Compression | Lossy (AAC) | Lossy (AAC); lossless when it holds ALAC |
| Usually contains | AAC with chapters | AAC, sometimes Apple Lossless |
| Introduced | The 2000s, by Apple | The early 2000s, by the Moving Picture Experts Group (popularised by Apple) |
| Opens in | Apple Books, iTunes and Music, VLC and most audiobook apps | Apple devices, Android, current browsers; some car stereos and older players do not |
| Best for | Audiobooks with chapters and a remembered playback position | Music and voice memos on Apple devices |
| File extension | .m4b | .m4a |
No. The M4B to M4A conversion runs inside your browser, on your own phone or computer. The file is not sent to ToAny or to anyone else.
M4A 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 M4A. 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.