About MKV (Matroska Video)
MKV — Matroska Video — is the container for people who care more about what a file can hold than where it can play. Fully open and endlessly flexible, it accepts virtually any video and audio format, plus multiple audio tracks, chapter marks, and soft subtitles. That is why OBS records to it (an MKV survives a crash mid-recording; an MP4 often doesn’t), and why it dominates the archiving and rip-management world.
The trade-off is reach. Phones, TVs, browsers, and editing timelines largely pretend MKV doesn’t exist. The standard fix is not to touch the video at all but to move it into an MP4 box — and because MKV files very often hold MP4-compatible video, that conversion here is usually a lossless repackage that finishes in seconds.
Convertmaxxing reads MKV and converts it out; it doesn’t create MKV files. One honest limitation: MP4 is a far stricter container, so only the primary video and audio track make the trip — extra languages and subtitle tracks stay behind.
Strengths
- Holds practically any codec, plus multiple audio tracks, chapters, and subtitles
- Crash-resilient recording — the reason OBS defaults to it
- Fully open standard with no licensing baggage
- Usually converts to MP4 losslessly — the video inside is often already compatible
Limitations
- Very limited playback support on phones, TVs, consoles, and the web
- Editing software support is inconsistent at best
- Its multi-track riches don’t survive conversion to stricter containers like MP4
- Creating MKV files isn’t supported here — converting out of MKV is the common need