Convert MP4 to M4B Online — Free
Fast, free MP4 to M4B converter. No registration required.
2M+ Files Converted
Trusted by thousands of users
Secure Transfer
HTTPS encrypted uploads
Privacy First
Files auto-deleted after processing
No Registration
Start converting instantly
Works Everywhere
Any browser, any device
How to Convert
Upload your .mp4 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 .m4b file when it's ready.
What is MP4?
MP4 is the most widely used video container format. It stores video, audio, subtitles, and metadata. Compatible with virtually every device and platform, from smartphones to smart TVs.
Format Details
- Full Name
- MPEG-4 Part 14
- Extension
- .mp4
Key Features
- Universal compatibility
- Streaming support
- Small file sizes
- Hardware-accelerated playback
What is M4B?
M4B is the MPEG-4 audiobook format used by Apple iTunes and many audiobook platforms. It supports chapter markers, bookmarking, and AAC compression for efficient audiobook delivery.
Format Details
- Full Name
- MPEG-4 Audiobook
- Extension
- .m4b
Key Features
- Chapter support
- Bookmark resume
- iTunes compatible
- AAC compression
MP4 vs M4B
| Feature | MP4 | M4B |
|---|---|---|
| Full Name | MPEG-4 Part 14 | MPEG-4 Audiobook |
| Extension | .mp4 | .m4b |
| Best For | Universal compatibility | Chapter support |