.mkv (Matroska Video) is a popular format for online video distribution (particularly through BitTorrent networks and all). It is an open and free container format. One of its advantages is that it can keep a number of video, audio, picture subtitle components in just one file.
One popular use of .mkv files is to store high-definition (HD) videos, in formats like H.264. Matroska video files end with the extension .mkv (may also contain audio and subtitle), while audio only files are .mka and subtitle files are .mks Typically, you would find a .mkv file – that is also what I have come across.
MKV container format is a fork of another format, after disagreements between its founders regarding some technical decisions. Most users of the original format moved to .mkv format after its developer went inactive, and .mkv has gained popularity ever since.
You can play .mkv files in Mac OS X using VLC player without downloading any additional codecs, but what if you need to convert and keep the file as a .mp4 video, for example, to play on other devices (like PS 3, iPod, Apple TV, iPhone etc.)?
Most solutions online (which also happen to be outdated and impractical) require Quicktime Pro and Perian, or other expensive mkv video converters, or has severe restrictions regarding the encoding types allowed within the .mkv container format. Some others use the command-line utilities, which may be acceptable if you are a total geek, or uses Windows software, in which case you will need access to Windows via Bootcamp/virtualization or a PC.
You have come to the right place if you are looking for an mkv to mp4 converter – this guide shows you how to convert .mkv video files to .mp4 files using a single open-source and free software, Handbrake.
Convert .mkv to .mp4
The latest version of Handbrake (0.93 or above) allows MKV source files. Then, you can convert the file to various supported formats like any other conversion using Handbrake. Note that Handbrake may have to re-encode and/or re-compress videos, and if this is the case, be prepared to leave your Mac on for processing for a considerable amount of time, as it will be time and resource-hungry.
Download Handbrake.

Open Handbrake, and you will be asked to enter a source. Select a file and continue with the conversion process.

I will update this post if I find any good tweaks or settings regarding the conversion. Meanwhile, leave a comment here if you have any difficulty in converting .mkv files to .mp4 and using it.
Related reading
- Tooble: download and convert YouTube videos for iPod
- Convert .flac files to .mp3 in Mac OS X
- How to convert AMR files to MP3
- How to convert WMA to MP3 audio (Mac OS X)
mac mkv conveter offers video conversion between any two video types in common video files.
http://www.mkvconverterformacos.com/