MP4 to MKV

MP4 to MKV features

• 01

  Open container for archiving

  Matroska is a free, open-standard container designed for long-term storage. It supports unlimited audio, subtitle, and chapter tracks — perfect for media libraries on Plex, Kodi, Jellyfin, or NAS systems.

• 02

  Quality slider for fine control

  Use the 1–100 slider to balance file size against visual fidelity. A setting of 75–85 produces files visually indistinguishable from the source on most screens.

• 03

  100% private, runs in your browser

  Powered by FFmpeg compiled to WebAssembly, conversion runs entirely on your machine. Your video never reaches a server and nothing is logged.

MP4 to MKV FAQ

How do I convert MP4 to MKV?

Drop your MP4 file onto the upload area (or click Choose file), adjust the quality slider if needed, then click Convert. Download the MKV file when conversion is complete.

Why convert MP4 to MKV?

MKV is preferred for media servers like Plex, Kodi, and Jellyfin because it supports unlimited audio tracks, chapters, and embedded subtitles. It's also the de facto standard for high-quality video archives.

What players can open MKV?

VLC, MPV, Plex, Kodi, Jellyfin, PotPlayer, and most modern media players. Web browsers and the default Windows/macOS players don't open MKV out of the box, so install VLC if you need universal playback.

Will I lose quality converting to MKV?

Some, since the file is re-encoded. At a quality setting of 80 or above, the difference is barely perceptible. Push the slider higher (95–100) for maximum fidelity.

Is my video uploaded to a server?

No. The converter runs entirely inside your browser using FFmpeg WebAssembly. Your video files never leave your device and nothing is stored or logged.