How To Split MKV files using MKVToolnix

In this tutorial we will look at how to split a large MKV file in to multiple parts and in a user specified size.  This will keep them in the same container without any loss in quality of audio or video. For this we will require a free program written by the very talented Moritz Bunkus called MKVToolnix. Once you have downloaded (I chose the installer, but the .7zip is there if you prefer) the program which for Windows users can be found at the bottom of the page, install it.

First select your language

step 1

Click Next

Step 2

Select the install path, by default it will be C:\

Step 3

Now click Install

Step 4

You will now be asked if you wish to add a shortcut for the program on your Desktop

Step 5

In the next window, you will be asked if you wish to use a GUI (graphical user interface) for MKVExtract. For the purposes of this tutorial, we are just splitting a .mkv file, and a GUI is included for this purpose. Click Next

Step 6

That’s the install finished. Next we will move on to the main window.

Step 7

When the program first opens, you will be greeted with the main window, with the Input tab selected. Click add and navigate to the mkv file that you wish to split. Highlight the file and hit Open.

select file

The file information will now be loaded. At the bottom you can also specify the path for the outputted files. I chose to keep then in the same folder, which is what it will default to.

Step 8

Next click on the Global tab, and check the Enable Splitting box. Just under this, make sure that …after this size: is selected and input the size of the largest split file that you require. Now for me, I wanted to enable the mkv to be played on a FAT32 file system, so it will have to be less than 4GB. I chose 3800M (MB) as my preferred split file size, but note that they may come out slightly larger so avoid choosing 3950M as that may run over the 4GB mark, which is what you want to avoid. Please note that you have to specify a size identifying letter after the numerical size:

  • G = Gigabyte (GB)
  • M = Megabyte (MB)
  • K = Kilobyte (KB)

Once you have selected your split file size, simply click Start Muxing at the bottom.

main settings

The program is very quick to work, but this will vary depending on your hardware specs.

step 10

Hopefully, you should have now successfully split your mkv file into separate files that will play in FAT32 file systems or for whatever reason you wanted to split them.

step 12

As you can see from the output folder, my 11.5GB.mkv file has now been split into 3 separate files. The video and audio quality is just as crisp, and the splits are spot on

finished look

Please note, that in this tutorial I was running Windows 7 Ultimate x64 with 4GB RAM on an Intel Core 2 Quad Q6600.

Logichaos also have a great tutorial on splitting MKV files that will also aid you in splitting files for YouTube, as well as having a great FAQ

MKVToolnix is available on the following platforms:

  • Arch
  • CentOS/RedHat
  • Debian
  • Fedora
  • FreeBSD
  • Gentoo
  • Mac OS X
  • Mandriva
  • NetBSD
  • Slackware
  • openSUSE
  • Ubuntu
  • Windows
  • Zenwalk
  • others

Well, I hope this has been of use to some of you. This program is simply fantastic and very quick, and has a ton of other features which I haven’t gone into, so have a play around.  Any questions, please feel free to ask in the comments.


  1. Dennis says:

    Helloo again!

    After splitting around 10 movies that all worked fine to play on my Oppo BDP-83 through an USB device i formated my hard drive and did a clean installation ov Windows 7. Then after i had installed the same version of MKVToolNIXnot one singel movie is playable on the USB device in my Oppo player. I have now tried the same version of the software that i had sucess with earlier and also a newer one and on 4 different movies but not one of them works. 2 of them starts but are blurry and it`s hardley that you see what is going on, and the other 2 is not starting at all. But every one of them is working fine on my PC after splitting.

    Any ides on this ?

    I was so happy that everything worked ok then, poof, nothing :(

  2. Dennis says:

    No one that have any thoughts about this, or if there is other formats to convert to that might work ?

  3. Very good tutorial. thanks for this :)

  4. This is perfect! – I’m so sick of using MKV2VOB

  5. Thank you very much! great software great guide!

  6. Vorpike says:

    I tried this, but somehow, I my files are even longer in duration, I can’t verify this by scrubbing through the video, because my .mkv is really laggy (the size, maybe)? Why is my 2 hour movie 7Gb? And is there another way to make it less laggy without splitting? If not, what did I do wrong as to make the video even laggier, and longer in length?


  1. […] larger that 4GB. I have written an article on how to split MKV files simply and for free using MKVSplit. Splitting then really doesn’t take long at […]

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