---
title: ".mkv file — what it is and how to open it"
description: "A .mkv file is a Matroska Video. An open container that holds any codec plus multiple audio tracks and subtitles. How to open one on Windows, macOS and Linux, and what to convert it to."
url: https://atoneplace.net/file/mkv/
site: "At One Place"
---

# .mkv files

**.mkv file: Matroska Video**

An open container that holds any codec plus multiple audio tracks and subtitles.

## What opens a .mkv file

- **Windows:** Media Player (built in), VLC, MPC-HC
- **macOS:** VLC, IINA, Elmedia Player
- **Linux:** VLC, mpv, Videos / Totem (built in)

## What a .mkv file is

Matroska is a free, open container standardised as RFC 9559 in 2024. It can wrap almost any video and audio codec and store several language tracks, chapters and embedded subtitles in one file, which is why ripped and downloaded films use it. Windows Media Player and VLC play MKV directly; the usual failure is a smart TV or older phone that only recognises MP4, in which case remuxing to MP4 takes seconds and does not re-encode.

## Converting it

A .mkv file is commonly converted to .mp4, .avi, .mov, .webm or .mp3. It is a binary format, so a text editor will show unreadable characters rather than its contents.

## Details

- **Extension:** .mkv
- **Full name:** Matroska Video
- **Category:** Video
- **MIME type:** video/matroska
- **Created by:** Matroska.org / IETF (RFC 9559)
- **Format:** Binary

## Common questions

### How do I open a .mkv file?

On Windows use Media Player (built in); on macOS use VLC; on Linux use VLC. An open container that holds any codec plus multiple audio tracks and subtitles.

### What is a .mkv file?

Matroska Video. Matroska is a free, open container standardised as RFC 9559 in 2024. It can wrap almost any video and audio codec and store several language tracks, chapters and embedded subtitles in one file, which is why ripped and downloaded films use it.

### Can I convert a .mkv file?

Yes. It is usually converted to .mp4, .avi, .mov, .webm or .mp3, either by exporting from one of the programs listed above or with a format converter.

## Related pages

- [.mp4 — MPEG-4 Part 14 Video](https://atoneplace.net/file/mp4/)
- [.mov — QuickTime Movie](https://atoneplace.net/file/mov/)
- [.avi — Audio Video Interleave](https://atoneplace.net/file/avi/)
- [.srt — SubRip Subtitle](https://atoneplace.net/file/srt/)
- [.webm — WebM Video](https://atoneplace.net/file/webm/)
- [.ts — MPEG Transport Stream](https://atoneplace.net/file/ts/)
- [.wmv — Windows Media Video](https://atoneplace.net/file/wmv/)
- [.mpg — MPEG-1 / MPEG-2 Video](https://atoneplace.net/file/mpg/)
- [.m4v — iTunes Video](https://atoneplace.net/file/m4v/)
- [.vtt — WebVTT Caption](https://atoneplace.net/file/vtt/)
- [.swf — Shockwave Flash Movie](https://atoneplace.net/file/swf/)
- [.mts — AVCHD Video](https://atoneplace.net/file/mts/)

## Sources

- Media Types Registry — IANA (https://www.iana.org/assignments/media-types/)
- Official vendor product documentation — At One Place (/about/)