WEBM to MKV Converter

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MP4, WebM, AVI, MPEG, MKV, FLV, OGG, MOV, M4V, WMV, ASF, 3GP and other video files
Max file size: 200MB

All uploaded files are automatically deleted 1 hour after upload.
For permanent links you can use: https://ezgif.com/webm-to-mkv?url=https://example.com/source-video.mp4

Free Online WEBM to MKV Converter

Convert WebM video files to Matroska (MKV) format instantly — no software to install, no registration, and no watermarks. Uploaded files are automatically deleted after one hour.

Lossless container conversion

Both WebM and MKV are based on the Matroska container specification. This means the video (VP9/VP8) and audio (Opus/Vorbis) streams can be copied directly into the MKV container without re-encoding, resulting in zero quality loss and instant processing. MKV offers broader compatibility with desktop media players like VLC, PotPlayer, and Plex/Kodi media servers.

Frequently asked questions

Is there any quality loss?

No. The streams are remuxed without re-encoding. The video and audio data remain identical to the original WebM file.

Why would I want MKV instead of WebM?

MKV is more widely recognized by desktop media players and supports additional features like embedded subtitles (SRT, ASS), chapter markers, and multiple audio tracks. WebM is better for web embedding.

Similar conversions: WebM to MP4, WebM to MOV, MKV to WebM.