How to convert MP4 to MKV
A simple browser-based way to convert an MP4 file to MKV, plus when the change makes sense.
Published
The short answer
You can convert an MP4 file to MKV when a player, editor, or archive workflow asks for MKV. The file extension changes the container. It does not promise that every device will play the new file.
MP4 and MKV are containers
A video file can hold several parts:
- video data
- audio data
- subtitles
- chapter information
MP4 and MKV are both container formats. A container is like a box for those parts.
Convert MP4 to MKV in three steps
- Drop the
.mp4file into Convert My. - Choose MKV from the available outputs.
- Select Convert & download.
The conversion happens in your browser. Keep the original file until you have checked the new one.
When MKV can help
MKV can be a useful choice when you want:
- a file for a media library that prefers MKV
- room for several audio tracks or subtitle tracks
- a container used by your video workflow
When to keep MP4 instead
Keep MP4 when you need a file that is widely accepted by phones, browsers, and sharing sites.
| Question | Practical answer |
|---|---|
| Do I need a different container for my media library? | MKV may help |
| Do I need broad phone and website support? | MP4 is usually safer |
| Will conversion fix a broken video codec? | Not always |
| Should I keep my original? | Yes |
Check the result
Open the downloaded file in the player or editor you plan to use. Check the picture, sound, and any subtitles you need.