FixFile
File Format

MKV (.mkv)

Matroska Video container — the most versatile open-source video format. Supports unlimited audio/subtitle tracks, chapters, and any codec. Preferred for HD movie storage.

Extension
.mkv
MIME Type
video/x-matroska

Last updated

Overview

MKV (Matroska Video) is an open-source multimedia container format based on the Matroska specification, which was created in 2002 as a technically superior alternative to AVI. Matroska means "nested doll" in Russian, reflecting the format's ability to nest multiple streams within a single file.

MKV can contain an unlimited number of video tracks, audio tracks (multiple languages), subtitle tracks (multiple languages, embedded or linked), chapters, menu structures, and metadata — all in a single file. It supports virtually any codec, including H.264, H.265/HEVC, AV1, VP9, AAC, FLAC, DTS, and more. These properties make it the preferred format for storing Blu-ray rips and high-quality video collections.

Common Uses

  • Blu-ray and 4K UHD remuxes — preserves all original audio tracks, subtitles, and chapters from disc media
  • HD movie archives — H.264 and HEVC-encoded movie collections
  • Anime distribution — the fansub community distributes translated anime almost exclusively in MKV with embedded subtitles
  • Video streaming servers — Plex, Jellyfin, and Emby serve MKV files efficiently over local networks

Advantages

  • Multiple tracks — unlimited audio, subtitle, and video streams in one file without quality loss
  • Open and free — no patents or royalty requirements for the container itself
  • Chapter support — built-in chapters enable DVD/Blu-ray-style navigation
  • Error recovery — damaged MKV files can often be partially played; seeking still works after corrupted sections
  • Future-proof — supports emerging codecs (AV1, VVC) without format changes

Limitations

  • Limited device support — smart TVs and game consoles may not support all codec combinations inside MKV
  • No DRM — cannot carry DRM-protected content (this is by design, not a technical limitation)
  • Large files — lossless or high-bitrate Blu-ray remuxes can exceed 50 GB per film

Supported Software

  • Desktop: VLC (all platforms), Kodi, Plex Media Server, MPC-HC, mpv
  • macOS: IINA, VLC, Infuse
  • Windows: VLC, MPC-HC, Windows Media Player (with codec pack)
  • Mobile: VLC (iOS/Android), Infuse (iOS), MX Player (Android)