M4B to APK Converter
Processing entirely on your device — large files may take a moment.
Repack an APK as ZIP to inspect its manifest and assets (not for reinstalling). If your files are still in M4B format, this page is the shortcut: M4B is the audiobook flavour of M4A — AAC audio with chapter markers, used by Audible and Apple Books.
This converter runs entirely in your browser using WebAssembly — your files never leave your device, nothing is uploaded, and there are no watermarks, sign-ups or queues. Drop in several files at once to convert them as a batch.
How M4B compares to APK
| M4B | APK | |
|---|---|---|
| Compression | Lossy AAC + chapters | DEFLATE / stored |
| Best for | Chaptered audiobooks | App inspection |
How to convert M4B to APK
- 1
Select your files
Select your M4B file — it never leaves your device.
- 2
Convert instantly
The engine packs the file, byte for byte, into a APK container — no re-encoding, no quality change.
- 3
Download results
Download the finished APK archive.
About the M4B format
M4B is M4A wearing an audiobook badge: the same AAC audio in an MP4 container, plus chapter markers that Apple Books and Audible apps render as a scrubbing timeline. Buy an audiobook outside Audible and it likely arrives as M4B.
The format is deliberately chained to Apple's book ecosystem. Converting M4B to MP3 sets the book free: car stereos, gym players, old iPods and every app without chapter support will play it — though the chapter marks themselves are flattened away.
+Strengths
- ✓Chapter markers survive on Apple platforms
- ✓Efficient AAC audio
!Limitations
- −Chapters vanish in MP3 conversion
- −Non-Apple support is patchy
About the APK format
An APK is Android’s install package: a ZIP holding AndroidManifest.xml, compiled DEX bytecode, native libraries and assets. Unpacking one is the standard first step of security review, compatibility checks and asset recovery.
One honest limit: unpacking is inspection, not installation — a repacked ZIP cannot be installed back onto a phone, and the page says so.
+Strengths
- ✓Everything an Android app ships
- ✓ZIP-based, easy to unpack
- ✓Manifest readable as XML
!Limitations
- −DEX bytecode is not human source
- −Repack cannot reinstall
Why convert M4B to APK?
Converting makes sense where the strengths of APK meet what M4B cannot give you. Everything an Android app ships Meanwhile Chapters vanish in MP3 conversion One pass through the converter above puts your file on the right side of that trade-off.
Frequently asked questions
Is this M4B to APK converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Is there a file size limit for M4B to APK?
The only limit is your device's memory, since nothing is uploaded. Files up to a few hundred megabytes work fine on a modern desktop browser; very large files simply take a little longer.
Can I convert a whole folder of M4B files?
You can select many files at once and they are processed in a single batch. Output files land in one ZIP download when there is more than one result.
Are tags like title and artist preserved?
Tag handling varies between target formats and this conversion focuses on the audio itself. For archival copies where tags matter, keep the original file; the converted copy is for playback and sharing.