Convert MP4 to Matroska
We turn MP4 into Matroska right in your browser — the file never goes to a server.
What you will lose
Nothing important: the target format does everything the source does.
How they differ
| MP4 | Matroska | |
|---|---|---|
| Lossless | no | yes |
| Lossy | yes | yes |
| Multichannel | yes | yes |
| Tags | yes | yes |
| Released | 2001 | 2002 |
| Author | MPEG | CoreCodec |
MP4
Good at
- Plays on everything: TVs, car stereos, phones a decade old
- Carries several audio tracks, subtitles and chapters in one file
- Streams well: playback starts before the file has finished loading
Awkward about
- Anything can be inside — the extension does not tell you if it will play
- The audio is almost always lossy, so it is not a master copy
- Editing without re-encoding is close to impossible in this container
Use it when
- The video is being sent or published and has to open for everyone
- Footage from a phone that people will simply watch
- One audio track is all you need
Matroska
Good at
- Takes anything inside: any codec, a dozen tracks, subtitle fonts
- The one common container people fill with lossless audio
- Tracks and subtitles can be swapped without touching the picture
Awkward about
- TVs and phones often refuse to open it
- No browser plays it directly
- Files run larger: what goes inside is usually less compressed
Use it when
- A home archive where everything should be kept as it was
- Several audio languages and subtitle tracks in one file
- The file is watched on a computer, not on household hardware
Common questions
- Does the file get uploaded to a server?
- Yes, this pair needs the server: browsers cannot encode that format. The file and the result are deleted within a couple of hours and never shared.
- Will surround sound survive?
- Yes, Matroska carries more than two channels — 5.1 stays 5.1.
- Can I get the original quality back afterwards?
- Yes, Matroska supports lossless compression, so you can go back to the original.
- How many files, and how large?
- Up to 3 files at a time, 500 MB each. No sign-up, no watermarks.