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MP4 to MKV

Convert an MP4 video to MKV in your browser. The video and sound are copied into the MKV as they are, and it’s free, with no watermark.

Files stay on your device

Drop files to convert

See their format, then choose an output.

MP4, MOV, MKV, WebM, MPEG-TS, and 3GP videos. You can also drag in a whole folder.

How to convert MP4 to MKV online

Open an MP4 and save it as a Matroska MKV for VLC, Plex, or Kodi. MKV can hold every video and audio track an MP4 can, so the MP4 to MKV converter copies them without re-encoding, and the file never leaves your device.

  1. Step 1

    Choose your MP4
    Pick an MP4 or drop it into the converter above.

  2. Step 2

    Keep MKV
    MKV is selected, and the tracks are copied without re-encoding.

  3. Step 3

    Download the MKV
    Save the MKV when it finishes. It opens in VLC, Plex, and Kodi.

What to expect

Supported inputs
MP4 videos and other readable video files.
What happens
Video and audio tracks are copied unchanged, so the picture and sound keep their quality. Subtitle tracks are left out.
Limits
QuickTime and the iPhone’s Photos app don’t open MKV files, so keep the MP4 for Apple devices.

Your files stay on your device

Your computer does the work, so the file never has to be uploaded, and that’s also why it’s free: there’s no server time for us to pay for. You don’t need an account, and nothing you make gets a watermark.

“Helped me in a pinch! Love your passion!”
Erick, a supporter

Questions

No. The video and sound are copied as they are, not re-encoded.

There is no upload limit because the file stays on your device. Very large files depend on your browser's memory and speed.

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