Add your MTS file
Drop one or more .mts files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
MTS to M4R
Pulling the soundtrack out of a .mts video into .m4r audio keeps what you can hear and drops the picture entirely. Free, private, and validated — the file never leaves your browser.
100% private for supported formats
Runs on your deviceConvert supported files
Drop MTS files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting AVCHD video to Apple ringtone
Pulling the soundtrack out of a .mts video into .m4r audio keeps what you can hear and drops the picture entirely. An .mts file is AVCHD footage as written to a camcorder's memory card, containing H.264 video inside an MPEG transport stream. Sony and Panasonic camcorders from the late 2000s onward filled SD cards with .mts clips, so the extension is familiar to anyone importing family or event video.
An .m4r file is an iPhone ringtone: AAC audio in an MPEG-4 container, identical to an .m4a in everything but the extension. Apple uses .m4r purely as a routing marker so iTunes and iOS file the audio under Tones instead of Music. For this route the practical draw is the only ringtone format iOS accepts and full AAC quality, indistinguishable from the source track — balanced against tones over 40 seconds are rejected outright, which is worth knowing before you commit a large batch.
Why convert MTS to M4R?
The usual reason to take .m4r audio out of a .mts file is that only the sound matters — a talk, interview, song, or podcast segment. Keeping the video stream would waste storage, and a dedicated audio file is easier to trim, tag, and play. On the source side, transport-stream packet overhead makes files larger than the same video in MP4; on the target side, the payoff is the only ringtone format iOS accepts, which is exactly what you want for turning a favorite song's hook into a custom iPhone ringtone.
MTS vs M4R at a glance
| Aspect | AVCHD video (.mts) | Apple ringtone (.m4r) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Lossy — discards detail it judges invisible to shrink files |
| How it stores data | uses 192-byte transport packets, standard 188-byte packets plus a 4-byte arrival timestamp, matching Blu-ray's BDAV layout | shares the ISO base media layout of .m4a, carrying AAC-LC audio |
| Strongest at | importing camcorder footage into Premiere, Resolve, or Final Cut | turning a favorite song's hook into a custom iPhone ringtone |
| Weak spot | transport-stream packet overhead makes files larger than the same video in MP4 | tones over 40 seconds are rejected outright |
| Metadata | recording date, camera settings, and GPS coordinates on some models are stored in the AVCHD folder's clip-info files rather than in the .mts stream itself | standard iTunes atoms apply, though iOS shows only the title in the ringtone picker |
Pick M4R as the output
Select .m4r in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if M4R is selectable, the route is real and validated.
Convert on your device
Press Convert. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid M4R file. Outputs keep the original filename with the .m4r extension.
MTS to M4R questions, answered
Will converting MTS to M4R lose quality?
Since mts is container-oriented and m4r is lossy-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .m4r itself requires.
Is it private to convert MTS files here?
Yes — the .mts file is processed inside your browser tab and never uploaded. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded. Close the tab and the file is gone from memory.
Where will the M4R file work?
iPhones accept .m4r only through iTunes or Finder sync and GarageBand export, and every Apple device can play it since the audio is ordinary AAC. Other platforms open the file happily after a rename, though Android sources its ringtones from plain MP3 or OGG instead.
Will the M4R file be bigger or smaller than my MTS?
Much smaller — the video stream is usually 80–95% of a .mts file's weight, and it is discarded entirely. The remaining audio is re-encoded at the bitrate implied by your quality setting.
What happens to the metadata in my MTS file?
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, recording date, camera settings, and GPS coordinates on some models are stored in the AVCHD folder's clip-info files rather than in the .mts stream itself; none of it is transmitted anywhere because the file never leaves your browser.