WebM to MKV

WebM to MKV features

• 01

  Built for media servers

  MKV is the format Plex, Kodi, Jellyfin, and most NAS-based media systems expect. Convert your WebM to MKV to drop it straight into your library with full metadata support.

• 02

  Quality slider for fine control

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

• 03

  100% private, runs in your browser

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

WebM to MKV FAQ

How do I convert WebM to MKV?

Drop your WebM 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 WebM to MKV?

MKV is the container format media servers like Plex, Kodi, and Jellyfin work best with. It supports unlimited audio tracks, chapters, embedded subtitles, and is ideal for long-term archival of high-quality video.

What plays MKV files?

VLC, MPV, Plex, Kodi, Jellyfin, PotPlayer, and most modern media players. Default Windows/macOS players and web browsers don't support MKV — install VLC for universal playback.

Will I lose quality converting WebM to MKV?

Some, since the video codec changes from VP9 to H.264. At a quality setting of 80 or above, the difference is barely perceptible. Push to 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.