The Matroska Multimedia Container is a free and open container format, a file format that can hold an unlimited number of video, audio, picture, or subtitle tracks in one file.[1] It is a universal format for storing common multimedia content, like movies or TV shows. Matroska is similar in concept to other containers like AVI, MP4, or Advanced Systems Format (ASF), but is entirely open in specification, with implementations consisting mostly of open source software. Matroska file extensions are .mkv for video (which may or may not include subtitles and audio), .mk3d for stereoscopic video, .mka for audio-only files, and .mks for subtitles only.[2]

MKV Extension Icon
Filename extension
.mkv .mk3d .mka .mks
Internet media type
video/x-matroska audio/x-matroska
Initial release6 December 2002; 18 years ago (2002-12-06)
Latest release
(18 February 2021; 3 months ago (2021-02-18))
Type of formatContainer format
Container forMultimedia
Extended fromMCF, EBML
Open format?yes

"Matroska" is derived from matryoshka (Russian: матрёшка [mɐˈtrʲɵʂkə]), the Russian word for the hollow wooden dolls which open to expose another smaller doll, that in turn opens to expose another doll, and so on. The logo writes it as "Matroška"; the letter š, an "s" with a caron over it, represents the "sh" sound (/ʂ/) in various languages.


The project was announced on 6 December 2002[3] as a fork of the Multimedia Container Format (MCF), after disagreements between MCF lead developer Lasse Kärkkäinen and soon-to-be Matroska founder Steve Lhomme about the use of the Extensible Binary Meta Language (EBML) instead of a binary format.[4] This coincided with a 6-month coding break by the MCF's lead developer for his military service, during which most of the community quickly migrated to the new project.[citation needed]

In 2010, it was announced that the WebM audio/video format would be based on a profile of the Matroska container format together with VP8 video and Vorbis audio.[5]

On 31 October 2014, Microsoft confirmed that Windows 10 would support HEVC and Matroska out of the box, according to a statement from Gabriel Aul, the leader of Microsoft Operating Systems Group's Data and Fundamentals Team.[6][7] Windows 10 Technical Preview Build 9860 added platform level support for HEVC and Matroska.[8][9]


The use of EBML allows extension for future format changes. The Matroska team has expressed some of their long-term goals on and Hydrogen Audio forums. Thus, the following are "goals", not necessarily existing features, of Matroska:[10]

  • Creating a modern, flexible, extensible, cross-platform multimedia container format
  • Developing robust streaming support (both this format and the WebM subset are streamable)[11]
  • Developing a menu system similar to that of DVDs based on EBML (as of July 2019, there is only a mostly empty draft)[12]
  • Developing a set of tools for the creation and editing of Matroska files (MKVToolNix, for example)
  • Developing libraries that can be used to allow developers to add Matroska support to their applications (made open source by Matroska developers)
  • Working with hardware manufacturers to include Matroska support in embedded multimedia devices


Matroska is supported by a non-profit organization (association loi 1901) in France,[13] and the specifications are open to everyone. The Matroska project is a royalty-free open standard that is free to use, and its technical specifications are available for private and commercial use. The Matroska development team licenses its libraries under the LGPL, with parsing and playback libraries available under BSD licenses.[10]

Compatible softwareEdit

See alsoEdit


  1. ^ Matroska v4 element specification, "TrackNumber: The track number as used in the Block Header (using more than 127 tracks is not encouraged, though the design allows an unlimited number)."
  2. ^ "Matroska FAQ - Q3: What file extensions does Matroska use?". Archived from the original on 2019-04-08. Retrieved 2018-07-16.
  3. ^ "Matroska: Older Archives". Archived from the original on 2017-08-03. Retrieved 2020-05-25.
  4. ^ Lhomme, Steve (2002-12-06). "Re: Proposed Spec Changes". Archived from the original on October 11, 2016. Retrieved May 23, 2016.
  5. ^ Frequently Asked Questions, the WebM project
  6. ^ Gabriel Aul (October 31, 2014). "HEVC also supported in-box". Twitter. Retrieved November 3, 2014.
  7. ^ John Callaham (November 1, 2014). "Microsoft: Windows 10 will support the HEVC video compression standard". Windows Central. Archived from the original on 2020-12-29. Retrieved 2020-05-25.
  8. ^ Bogdan Popa (November 3, 2014). "Microsoft Confirms MKV File Support in Windows 10". Softpedia. Archived from the original on 2017-10-05. Retrieved 2020-05-25.
  9. ^ Gabe Aul (November 12, 2014). "New build available to the Windows Insider Program". Microsoft. Archived from the original on March 3, 2015. Retrieved November 15, 2014.
  10. ^ a b "What is Matroska?". Archived from the original on 2020-12-29. Retrieved 2020-05-25.
  11. ^ "Streaming". Archived from the original on 2020-12-29. Retrieved 2019-06-30.
  12. ^ "Menu Specifications". Archived from the original on 29 December 2020. Retrieved 30 June 2019.
  13. ^ "Legal Aspect - Matroska". Archived from the original on 2020-12-29. Retrieved 2020-08-01.

External linksEdit