MTS to F4B Converter
Processing entirely on your device — large files may take a moment.
AVCHD Video and Adobe Flash Audiobook (F4B) exist for different jobs: MTS is the raw AVCHD clip format Sony/Canon camcorders write — high-bitrate H.264 transport streams straight off the memory card. Convert F4B audiobooks exactly like M4B — to MP3, M4A or WAV.
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 MTS compares to F4B
| MTS | F4B | |
|---|---|---|
| Compatibility | ffmpeg, VLC, Premiere | Apple Books, Audible |
| Best for | Camcorder footage ingestion | Chaptered audiobooks |
How to convert MTS to F4B
- 1
Select your files
Select your MTS video.
- 2
Convert instantly
The engine demuxes the container and encodes the audio track into your chosen format.
- 3
Download results
Download the F4B audio — the video track is simply dropped.
About the MTS format
MTS is what actually comes off a Sony or Canon AVCHD camcorder's memory card: high-bitrate H.264 transport streams with AC-3/PCM audio, often split across a BDMV folder structure. The video inside is excellent — the container is what edit software refuses to import.
Converting MTS to MP4 remuxes or re-encodes into a container every device opens. Stream-copy is possible when the H.264 profile is baseline-compatible; otherwise a light re-encode fixes compatibility without visible loss.
+Strengths
- ✓Native camcorder quality (24-28 Mbps)
- ✓Audio in AC-3/PCM survives remux
- ✓ffmpeg handles the transport stream natively
!Limitations
- −AVCHD H.264 profiles not always stream-copyable
- −Interlaced variants need deinterlacing
- −60p modes confuse older editors
About the F4B 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
Why convert MTS to F4B?
There is a concrete reason this conversion exists: AVCHD H.264 profiles not always stream-copyable F4B sidesteps that — Chapter markers survive on Apple platforms If that is your situation, the tool above settles it in seconds, entirely on your device.
Frequently asked questions
Is this MTS to F4B 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 MTS to F4B?
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.
Why is video conversion slower than image conversion?
Every frame has to be decoded and re-encoded. This site runs that work on your own CPU via WebAssembly — nothing is uploaded, but a multi-minute video reasonably takes a few minutes. Images, by comparison, are single-frame jobs.
Does converting MTS to F4B re-encode my video?
Yes. The video is decoded and re-encoded with the settings chosen by the quality slider, which is what allows the format and size to change. For an archival copy, keep higher quality; for sharing, lower quality gives a much smaller file.