What is a .MKV file? (How to open & convert)
Learn what .MKV is, how to open it, and use an embedded local-only tool for common tasks.
.MKV MKV is a flexible, open-standard video container format. It is widely used for high-definition movies because it can hold an unlimited number of video, audio, picture, or subtitle tracks in one file. However, many native TV players and mobile devices still lack full MKV support, making conversion to MP4 a common necessity.
Basic info
- Full name: Matroska Video Container
- Developer: Matroska.org (Open Standard)
- Category: Video
How to open a .MKV file
On macOS: Requires VLC or IINA; not natively supported by QuickTime Player.
On Windows: Supported by VLC Media Player, PotPlayer, or modern Windows Media Player with the correct codecs. Use our local tool to convert it to MP4 for broader device compatibility.
On mobile: Standard mobile players often struggle with high-bitrate MKV files; third-party apps like MX Player or VLC are recommended.
Try a related tool
Use a local-only tool (no uploads) for common tasks.
Related extensions
Browse similar formats in the Wiki.
Technical characteristics
- Supports advanced features like chapters, menu systems, and multiple audio streams.
- Extremely robust; handles errors better than MP4 or AVI containers.
- An open-source format, meaning it is not restricted by proprietary licensing.
Common scenarios
- Converting movie downloads to MP4 for playback on a Smart TV or tablet.
- Extracting specific audio or subtitle tracks from a multi-track MKV file.
- Reducing the file size of high-quality Blu-ray rips for easier storage.
Security notes
Safe. Like other video containers, MKV files carry data and do not execute code. Always ensure you download media from trusted sources.