Video format

MKV converter

An .mkv file uses the Matroska container, an open format designed to hold an unlimited number of video, audio, and subtitle tracks in one file. Collectors of high-quality rips and archival copies favor .mkv because it keeps every language track, chapter marker, and font attachment together.

Private for supported formats — processed in your browser

Convert supported files

Runs on your device

Drop MKV files here

Batch files can each use a different output. Nothing uploads for local conversions.

Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.

Where MKV comes from

Matroska began in 2002 as an open-source fork of the Multimedia Container Format project, taking its name from the Russian nesting doll. Google later chose a subset of Matroska as the foundation for WebM in 2010, which carried its architecture into every browser.

How MKV works

Built on EBML, a binary XML-like structure that lets the container gain features without breaking older parsers
Accepts virtually any codec: H.264, HEVC, AV1, VP9, FLAC, TrueHD, and styled SubStation Alpha subtitles
Chapters, multiple named editions, and file attachments such as fonts and cover art are all part of the specification
Error-tolerant design lets players recover footage from partially downloaded or truncated files

When to use MKV

Archiving discs while preserving every audio track and subtitle stream
Storing anime with styled subtitles and their embedded fonts
Keeping lossless FLAC or TrueHD soundtracks attached to their video
Acting as the source file for browser-side conversion to MP4 or WebM

Strengths and limitations

Strengths

Holds essentially any combination of codecs and track types
Fully open and royalty-free specification
Chapters, editions, and attachments have no equivalent in MP4
Truncated downloads often remain partially playable

Limitations

Safari and iOS refuse the container outright
Smart TVs support only certain codec combinations inside it
Several editing applications import Matroska poorly or not at all

Compatibility

Chrome, Firefox, and Edge can play Matroska files whose codecs they support, but Safari rejects the container on both macOS and iOS. VLC, mpv, and Plex handle .mkv everywhere, and Windows has shipped native Matroska playback since Windows 10.

Matroska tags cover title, cast, and arbitrary key-value pairs, and the container can embed cover art and other files as attachments.