MP4 to MTS Converter

What happens when you convert MP4 to MTS

• If the video inside the MP4 is already H.264, the tool first copies the streams straight into the MTS. That takes seconds and loses nothing.
• If a copy is not possible, it re-encodes to H.264 video with Dolby Digital (AC-3) audio at 48 kHz, in a transport stream with the 192-byte packets of AVCHD and Blu-ray, which is slow in a browser: expect several times the video's length for HD footage, less at lower resolutions.
• The MTS is a single video file like the ones an AVCHD camera records; it plays in VLC, on smart TVs and in video editors, but it is not the folder structure of an AVCHD card or a Blu-ray disc.

How to convert MP4 to MTS online

1. Press "Choose MP4 files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
2. Adjust the settings if you need to: resolution and quality control the size of the result. The defaults suit most people.
3. Press "Convert to MTS". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
4. Save each MTS with its download button. Close the tab and every trace of the files is gone from memory.

Why convert MP4 to MTS?

MP4 files usually come from phone videos, YouTube uploads, social media and streaming. People convert them to MTS because MTS is the file type AVCHD camcorders record, and video editors and smart TVs that handle camcorder footage read it.

In short, MP4 is good at what it was made for, and MTS is the more practical choice when the file has to play, upload or edit somewhere else. MP4 plays in every browser, phone and smart TV, while MTS does not play in browsers; plays in VLC and camera software.

How to convert MP4 to MTS on Windows, Mac, iPhone and Android

On Windows

Open this page in Chrome, Edge or Firefox, drag your MP4 files in from File Explorer, and press Convert. Each MTS is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert MP4 to MTS: choose Media, then Convert / Save.

On a Mac

Safari, Chrome and Firefox all work. Drag the MP4 files from Finder onto the drop zone and the MTS files land in Downloads.

On iPhone and iPad

Open the page in Safari and tap Choose MP4 files. You can pick from Photos or from the Files app. The converted MTS appears in Files, in the Downloads folder; to put it in your photo library, open it there, tap Share and choose Save Video.

On Android

Open the page in Chrome, tap Choose MP4 files and pick them from Files or your gallery. The MTS is saved to the Download folder, where any file manager can find it. Keep the screen on while a long video converts, because Android may pause a tab in the background.

Best settings for MP4 to MTS

Leave Resolution on Keep original and Quality on Standard if the video only needs to change container: that is what lets the tool copy the H.264 stream straight into the MTS, which is fast and loses nothing.

If the file is too big, change either setting and the video is re-encoded with H.264. Quality uses the CRF scale: High is 20, Standard 23 and Smaller file 28. As a rule of thumb each step of about 6 on that scale halves or doubles the size. Dropping from 1080p to 720p usually saves more than lowering the quality, and it also makes the conversion much faster.

MP4 vs MTS: the differences

About MP4 and MTS files

What is an MP4 file?

MP4 is the most widely supported video format, and H.264 video with AAC audio inside it plays on essentially every device made in the last fifteen years.

What is an MTS file?

MTS is the AVCHD recording format of HD camcorders from about 2006 to 2015, often interlaced at 1080i. The video inside is H.264, so it can usually move to MP4 without re-encoding.

MP4 to MTS not working? Common problems

• The conversion is slow. Audio and container changes take seconds, but re-encoding video runs on your own processor. Lower the resolution to 720p, close other tabs, and keep the device plugged in.
• The tab stops or reloads on a very large file. Browsers limit how much memory one tab can use, around 2 GB and less on phones. Split long recordings or convert them on a computer.
• The MTS will not play on an old device. Try the other formats offered for MP4, or choose 720p, which older players handle more reliably.

Convert MP4 to MTS with ffmpeg

This converter runs ffmpeg inside your browser. If you would rather use the ffmpeg command line on your own computer, this command produces an equivalent MTS with the same kind of settings:

ffmpeg -i input.mp4 -c:v libx264 -crf 23 -preset veryfast -c:a ac3 -b:a 192k -ar 48000 -f mpegts -mpegts_m2ts_mode 1 output.mts

Replace input.mp4 with the name of your file. For a whole folder of MP4 files, run the command in a loop, or drop them all on the converter above, which processes them one after another.