How to convert WEBM to MKV
- Add your .WEBM file - drop it in the box above or click to browse.
- Convert it to .MKV in a few seconds.
- Download your new .MKV file.
What to expect
- This is a remux, not a re-encode - video and audio are copied byte-for-byte, so there is no quality loss.
- Codecs do not change: the output
.mkvstill contains VP8/VP9/AV1 video and Vorbis/Opus audio; only the container changes. - MKV is a desktop format - browsers cannot play it as a video source, so keep the original
.webmif you need web embedding.
Frequently asked questions
Does converting WEBM to MKV reduce quality?
No - remuxing copies streams without decoding them, so quality is bit-for-bit identical to the source.
Why is the conversion so fast?
No decoding or re-encoding happens; only the container metadata is rewritten, so speed is limited by disk write speed, not CPU.
Will my media player support the output MKV?
Yes - MKV is widely supported by desktop players like VLC and mpv, and by most video editors.
Can I add subtitles or extra audio tracks during conversion?
Yes - in MKVToolNix drag in additional subtitle or audio files before multiplexing, and they all end up in one
.mkv.Programs that convert WEBM: Miro Video Converter · Free Studio · Freemake Video Converter · MediaCoder · SUPER · Miro Video Converter for Mac
