.mkv — Matroska Video
A flexible open video container often used for high-quality movies, subtitles, and multiple audio tracks.
About this format
MKV is a container, not a codec. It can hold video, audio, subtitles, chapters, attachments, and metadata in one file.
Use MKV when you need a rich local media container. Convert to MP4 or WebM when you need broad browser or platform upload support.
Real-world samples & file sizes
Four freshly sourced public video clips remuxed into real .mkv files. Each card uses a poster frame because browsers often do not play Matroska directly; the download link points to the actual MKV container.
Rain Clip remuxed to MKV
A short rain scene remuxed into a real Matroska container.
Sintel Extract remuxed to MKV
A 20-second animated film extract remuxed into MKV.
Big Buck Bunny MCU remuxed to MKV
A compact Blender open movie clip remuxed into MKV.
Cymatics demo remuxed to MKV
A 1080p cymatics experiment clip remuxed into MKV.
Pros
- +Supports many codecs and subtitle tracks
- +Good for local libraries and archival video
- +Open container design
Cons
- −Not accepted by many web upload forms
- −Browser playback is limited
- −Compatibility depends on the codecs inside
MKV vs other formats
| vs | Size | Quality | Note |
|---|---|---|---|
| MP4 | Similar with same codec | Container does not set quality | MP4 wins on device and browser compatibility. |
| WebM | Similar with same bitrate | Depends on codec | WebM is more web-focused; MKV is more flexible. |
Where it works
- Windows with Movies & TV or codecs
- macOS via VLC/IINA
- Linux media players
- Limited direct browser support
- Chrome may play some codec combinations
- Safari support is poor
- VLC
- IINA
- mpv
- Plex
- HandBrake
Related tools
Frequently asked questions
- Why will one MKV play and another fail?
- MKV is only the container. Playback also depends on the video and audio codecs stored inside it.
- Is MKV good for websites?
- Usually no. Convert to MP4 or WebM for web delivery.
Sources
- Matroska official documentation - Matroska container design and technical notes
- Library of Congress - Matroska multimedia container - Matroska/MKV archival format description
Other video formats
- .webm WebMGoogle's open, royalty-free video format for the web — typically 30-50% smaller than equivalent MP4 / H.264.
- .mov MOVApple's QuickTime movie container, common in camera exports, editing apps, and macOS workflows.
- .avi AVIAn older Windows video container that still appears in legacy cameras, screen recorders, and archives.