MP4 to MKV
The box that will hold everything at once
…
- 1
Why anyone leaves an MP4
Because you want more in the box. MKV will carry several audio tracks, a pile of subtitle tracks and chapter marks in one file, and MP4 is awkward or unwilling about all three.
- 2
Who is asking for it
Usually a home media library. Plex, Jellyfin and Kodi all treat MKV as the native shape of a film with alternate audio and switchable subtitles, because it is the only common container that holds them comfortably.
- 3
What it costs
Almost nothing. The picture inside an MP4 is a picture an MKV holds happily, so the frames move across rather than being re-encoded, and the file lands in seconds at the same quality.
FAQ
- How do I convert MP4 to MKV?
- Drop the file on this page and press the button. It runs in your browser, so there is no upload, no account and no daily limit.
- Why would I want an MKV?
- For what it holds. Several audio languages, several subtitle tracks and chapter marks in a single file, which is why media libraries prefer it and why MP4 keeps sending people this way.
- Does the quality drop?
- No. MKV holds the same picture the MP4 was carrying, so the frames are moved rather than encoded again.
- Will it play on my TV or phone?
- Less reliably than the MP4 did. This is the trade: you gain what the box can hold and you lose the thing MP4 is unmatched at, which is opening anywhere without being asked twice.
- Can I add subtitles here?
- No. This page changes the container the video is in. It does not add tracks, and it cannot invent ones the MP4 was not already carrying.
- Is the file uploaded?
- No. The video is opened and written back out in the page. No request carries it anywhere, which the network panel will show you while it runs.