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.
Pulling the soundtrack out of a .mts video into .aiff audio keeps what you can hear and drops the picture entirely. Free, private, and validated — the file never leaves your browser.
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.Pulling the soundtrack out of a .mts video into .aiff 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 .aiff file is Apple's Audio Interchange File Format, storing uncompressed PCM audio much as WAV does on Windows. Mac-based studios have exchanged .aiff masters for decades, and Logic Pro sessions and sample libraries remain full of them. For this route the practical draw is bit-perfect audio identical in fidelity to WAV and loop and marker metadata that samplers actually read — balanced against as bulky as any uncompressed format, which is worth knowing before you commit a large batch.
The usual reason to take .aiff 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 bit-perfect audio identical in fidelity to WAV, which is exactly what you want for delivering masters from macOS-based studios.
| Aspect | AVCHD video (.mts) | Audio Interchange File (.aiff) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Lossless — every pixel or sample is preserved exactly |
| 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 | classic AIFF stores big-endian PCM, the opposite byte order from WAV, in COMM and SSND chunks |
| Strongest at | importing camcorder footage into Premiere, Resolve, or Final Cut | delivering masters from macOS-based studios |
| Weak spot | transport-stream packet overhead makes files larger than the same video in MP4 | as bulky as any uncompressed format |
| 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 | nAME, AUTH, and ANNO chunks provide basic text, marker and instrument chunks store loop data, and an ID3 chunk is a common unofficial extension used by iTunes |
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.
Select .aiff in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if AIFF is selectable, the route is real and validated.
Press Convert. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded.
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid AIFF file. Outputs keep the original filename with the .aiff extension.
Since mts is container-oriented and aiff is lossless-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .aiff itself requires.
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.
macOS and all serious audio software open .aiff without hesitation, and Windows editors generally support it even though WAV is their default. Browsers offer partial support at best, and the format's size makes it a poor web choice regardless.
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.
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.