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 3GP
Pulling the soundtrack out of a .mts video into .3gp audio keeps what you can hear and drops the picture entirely. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
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 3GPP video
Pulling the soundtrack out of a .mts video into .3gp 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.
A .3gp file is a lightweight container defined by the 3GPP standards body for video recorded and shared on mobile phones. It packs low-bitrate video and compressed speech with minimal overhead, which made .3gp the format of MMS messages and early camera phones. For this route the practical draw is extremely small files by design and structural kinship with MP4 makes conversion quick — balanced against picture quality is poor by any modern standard, which is worth knowing before you commit a large batch.
Why convert MTS to 3GP?
The usual reason to take .3gp 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 extremely small files by design, which is exactly what you want for recovering videos from old feature phones and their memory cards.
MTS vs 3GP at a glance
| Aspect | AVCHD video (.mts) | 3GPP video (.3gp) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Container — quality depends on the codecs and settings inside |
| 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 | iSO base media structure like MP4, but with a deliberately restricted codec list |
| Strongest at | importing camcorder footage into Premiere, Resolve, or Final Cut | recovering videos from old feature phones and their memory cards |
| Weak spot | transport-stream packet overhead makes files larger than the same video in MP4 | picture quality is poor by any modern standard |
| 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 | a small set of 3GPP-defined asset atoms for title, author, and location exists, though most recording phones never wrote them |
Pick 3GP as the output
Select .3gp in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if 3GP 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 3GP file. Outputs keep the original filename with the .3gp extension.
MTS to 3GP questions, answered
Will converting MTS to 3GP lose quality?
Since mts is container-oriented and 3gp is container-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .3gp 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 3GP file work?
Android still opens most .3gp files, and desktop players such as VLC handle them, but iOS and web browsers generally do not. Because the codecs inside are dated, converting to MP4 with AAC audio is the standard path to modern playback.
Will the 3GP 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.
Can I convert 3GP back to MTS?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .mts → .3gp → .mts is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.