Convert MPEG-4 Audiobook (.m4b) to iPad Audio (.ipad-audio) online for free. Fast, secure audio conversion with no watermarks or registration.
Upload your .m4b file by dragging it into the upload area or clicking to browse.
Choose your output settings. The default settings work great for most files.
Click Convert and download your .m4a file when it's ready.
iPad plays M4B audiobooks natively through Apple Books with full chapter navigation, bookmarking, and playback speed controls. Converting M4B to iPad Audio (M4A or AAC) is usually unnecessary unless you specifically want the audiobook to appear in the Music app instead of Books, or you need to strip DRM from older Audible purchases (which requires separate tools). This conversion removes chapter markers and bookmark support, trading audiobook features for compatibility with the Music app's library.
Some users prefer managing all audio — music and audiobooks — in a single app (Music) rather than splitting between Music and Books. Others may want to share audiobook segments without the M4B format's association with DRM-protected content. Teachers may want to extract specific chapters as standalone M4A files for classroom use. iPad DJ apps and audio production apps also accept M4A but not M4B.
FFmpeg reads the M4B and either stream-copies the AAC audio into an M4A container (lossless, instant) or re-encodes at a different bitrate. The M4A output uses standard iTunes metadata atoms. iPad recognizes M4A as a music file, displaying it in the Music app rather than Apple Books. For chapter extraction, FFmpeg can split at chapter boundaries using the M4B's embedded chapter metadata.
With stream copy: identical to M4B. The AAC audio data is transferred bit-for-bit. With re-encoding: minimal quality change for spoken word at matching bitrates. M4B speech audio (32-64 kbps AAC) converts cleanly.
| Device | M4B | iPad Audio |
|---|---|---|
| Windows PC | Partial | Partial |
| macOS | Partial | Partial |
| iPhone/iPad | Partial | Partial |
| Android | Partial | Partial |
| Linux | Partial | Partial |
| Web Browser | No |
Resolution: N/A
Bitrate: 320 kbps
OGG Vorbis preferred
Resolution: N/A
Bitrate: 256 kbps
AAC format required
Resolution: N/A
Bitrate: 128 kbps
Lossless FLAC/WAV for best quality
Resolution: N/A
Bitrate: 128 kbps
MP3 mono for spoken word
M4B to iPad Audio is primarily about changing how iPad categorizes the content (Books vs Music). Use stream copy for lossless conversion, and split by chapter if needed.
安全な転送
HTTPS暗号化アップロード
プライバシー優先
処理後にファイルを自動削除
登録不要
すぐに変換を開始
どこでも動作
あらゆるブラウザ、あらゆるデバイス
| No |
| 特徴 | M4B | iPad Audio |
|---|---|---|
| 正式名称 | MPEG-4 Audiobook | iPad Compatible Audio |
| 拡張子 | .m4b | .m4a |
| 最適な用途 | Chapter support | iPad optimized |