MTS to MP4 Converter For AVCHD camcorder files
MTS and M2TS are AVCHD, the format Sony, Panasonic, Canon and JVC camcorders record to. The clips hide inside a PRIVATE, AVCHD, BDMV, STREAM folder chain, they are large, and almost nothing outside a media player will open them. This page rebuilds them as H.264 MP4 with AAC audio inside your browser tab. Know this before you start: AVCHD is always fully re-encoded here, so it is the slowest conversion on the site.
- MTS and M2TS
- Nothing uploaded
- Up to 1 GB per file
Convert MTS to MP4
MP4, MOV, M4V, MKV, AVI, WMV, WebM, TS, MTS and more
Up to 20 clips at once
Privacy-first. No uploads. If this helps, share it.
- The recording never leaves your device
Your browser reads the clip straight off the card or the disk and does all the work locally. Camcorder cards hold weddings, christenings, hospital visits and school concerts, which is the last kind of footage that should be sitting in a stranger's upload queue.
- Built around what AVCHD actually is
An MTS file is an MPEG transport stream carrying H.264 video and usually Dolby Digital audio, laid out for continuous recording rather than for sitting on a disk. It comes back as a plain MP4 with AAC audio and its index written to the front, so players can seek it instead of stumbling through it.
- Honest about the wait
AVCHD is not repackaged here, so every clip takes the full re-encode path on a single browser thread. Budget at least the running time of the footage, plug the laptop in, and leave the tab in front. This is the slowest tool on the site and pretending otherwise would only waste your afternoon.
How to convert MTS to MP4
On the card, or on the folder you copied off it, open PRIVATE, then AVCHD, then BDMV, then STREAM. The numbered files in there, 00000.MTS upward, are the clips. Drag them into the box at the top of this page and each one is re-encoded to H.264 MP4 with AAC audio on your own machine, then you download it. Nothing is sent to a server, and the real cost is time, because AVCHD always takes the long route.
- Open the STREAM folder
- Drop the MTS files in
- Download the MP4
MTS vs MP4: what actually changes
MTS and M2TS are closely related AVCHD transport stream variants. Both are MPEG transport streams, a shape built for broadcasting and for recording without a known end, where a player is expected to join partway through and work out what is going on. MP4 was built for the opposite job: one finished file on a disk, with a map at the front telling players where everything is. That difference, not the picture, is what this conversion is really about.
| What changes | MTS or M2TS (AVCHD) | MP4 output |
|---|---|---|
| Container | MPEG transport stream. Camcorders write it as .MTS on the card, while import tools and Blu-ray discs write the same stream as .M2TS | MP4, one self contained file with its index at the front, so playback can start before the whole file has been read |
| Video codec | H.264 already, held at a high and nearly constant camcorder bitrate whether the shot is a still landscape or a football match | H.264 again, re-encoded to a quality target rather than a fixed bitrate, so the encoder spends data where the picture needs it |
| Audio codec | Dolby Digital AC-3, or uncompressed PCM on some models, neither of which plays reliably out of an ordinary MP4 | AAC, the audio every browser, phone, TV and editor is safe to assume will play |
| Where it plays | The camcorder itself, VLC, and editors that know AVCHD. Phones, browsers, Photos apps and upload forms usually refuse it outright | Phones, browsers, smart TVs, social uploads, editors, cloud drive previews, slide decks and messaging apps |
| File size | Large. At the higher recording modes a gigabyte covers minutes rather than hours, which is why a card fills so fast | Usually smaller, because the quality target lets calm shots use less than the camcorder gave them. Smaller is the normal outcome, not a promise |
The row a table cannot show is timing. A transport stream carries its own clocks and packet structure meant for a recorder, and that is the part that makes players stutter, scrub badly or report the wrong duration. Rebuilding the file is what settles it, and it is why AVCHD is never simply repackaged here.
Whether converting AVCHD is worth it at all
If your whole workflow is VLC on one computer and an editor that already imports AVCHD, you do not need this page. MTS is worth converting when the footage has to leave that setup: onto a phone, into a group chat, up to YouTube or Drive, into a slide deck, onto a TV stick, or into an archive you want to still open in ten years without hunting for a player. The honest cost is that AVCHD is always fully re-encoded, so you pay real time and one generation of quality for a file that opens everywhere and usually takes up less room.
If the footage is going to be edited properly, import the MTS into your editor as it is and convert only the finished cut. Converting first adds a generation of encoding before the edit has even started, and gains you nothing your editor was not already doing.
Where the MP4 plays, and what it will not fix
H.264 video with AAC audio in an MP4 is the most widely supported combination in consumer video. Expect it to open on iPhone and Android, in Windows and macOS players, in browsers, on smart TVs and streaming sticks, in Instagram, YouTube and Facebook uploads, in Google Drive and Dropbox previews, and in PowerPoint and Keynote. What a conversion cannot do is change the footage itself, and AVCHD carries a few habits that travel with it.
Interlacing is not removed. There is no deinterlace control here, so footage shot in a 1080i mode can still show fine comb lines on fast motion, in the MP4 exactly as in the original.
Camcorders break long recordings into numbered parts on the card. Each part converts on its own, and this tool cannot join them back into one MP4.
Nothing here trims, crops or changes the frame. A 40 minute recording comes out 40 minutes long, and standard definition footage keeps the shape it arrived in.
Convert a camcorder file in three steps
Nothing is uploaded at any point.
Find the real video files
Open PRIVATE, then AVCHD, then BDMV, then STREAM. The numbered files in there are your clips, in recording order. On a Mac the AVCHD item often looks like a single file, so right click it and choose Show Package Contents to get inside. Copying STREAM to your desktop first is worth it, because working over a card reader is slow and cards drop out.
Drop them in and leave the tab alone
Up to 20 files per batch and 1 GB each. Only one clip encodes at a time, because the browser build runs on a single thread. The To dropdown is set to MP4; switch it to MP3 if the sound of a recording was all you were after.
Download the MP4
Take each result as it finishes, or all of them as a zip at the end. H.264 video, AAC audio, no watermark, no account and no expiring link.
Why do this in a browser tab
Camcorder footage has two awkward properties at once: it is personal, and it is enormous. Both of them argue against the usual answer of uploading it somewhere.
A family archive is not sample data
The reason people still own a camcorder is the reason the footage matters: birthdays, a school play, a grandparent talking, a holiday nobody else recorded. Handing that to an upload based converter to change a container is a poor bargain, and it cannot be taken back once sent.
Moving gigabytes is its own cost
Set privacy aside and the arithmetic still favours local work. Pushing a multi gigabyte MTS up a home connection, waiting in a processing queue and pulling the result back down often takes as long as the encode itself, or longer. Here the file is already on the machine doing the work.
Nothing to install for a one off card
The standard advice for AVCHD is to install a desktop converter, which is sensible if you shoot regularly and awkward if you have one old card and a borrowed laptop. Free desktop converters also vary a lot in what else they install and whether they mark the output. This one is a web page.
A shoot is never one file
Cards come back with a STREAM folder full of numbered clips, not a single recording. Select the lot, up to 20 per batch, and let the queue work through them while you do something else.
Home video is the most private video there is
What sits on a camcorder card tends to be the footage people would least like copied: children, family occasions, a funeral, a hospital room, a house being walked through. It is also footage with no backup half the time, which makes handing the only copy to an unknown server worse again.
This page does the decoding and encoding itself, in the tab, using a WebAssembly build of FFmpeg. Your clip is opened from your own disk and the finished MP4 is written back to it, with no server in between at any point, and no account to attach a history to.
What that means in practice
- The footage is read from your disk and stays there
- Neither the video nor its file name reaches us
- No sign in, no watermark, nothing to delete afterwards
- Your own processor does the encoding, so long footage takes long
MTS and AVCHD troubleshooting
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Open toolFrequently asked questions
An MTS file is one clip from an AVCHD camcorder. Inside it is an MPEG transport stream carrying H.264 video and usually Dolby Digital audio, written by Sony, Panasonic, Canon and JVC models into a PRIVATE, AVCHD, BDMV, STREAM folder chain on the memory card.
AVCHD folder paths and tool limits last reviewed on 15 August 2026.