WebM – Web Media Container
WebM is optimized for HTML5 video on the web. It often produces efficient files with VP9 or AV1 video and Opus audio.
WebM Converter →WebM to MKV
Convert WebM to MKV online in your browser. Upload video files and download individually or as a ZIP.
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to
To
Select your videos to convert
or drop MP4, WebM, MOV & MKV here (max 30 MB each)
Privacy
On your device only
Max size
30 MB per file
Speed
Multi-core when available
Format reference and conversion types
Formats involved
| Feature | WebM | MKV |
|---|---|---|
| Best for | Web streaming | Archiving & subs |
| Typical codec | VP9 / AV1 | Flexible |
| Browser support | Very good | Limited |
| Streaming | ✓ | ✕ |
MKV – Matroska Video
MKV is a flexible container that can hold multiple audio tracks, subtitles, and high quality video in one file.
MKV Converter →