5  /  1337 Reviews
Nov 13, 2022 Last updated


Older Versions

# Change Log

# Version 72.0.0 "Minuano (Six-eight)" 2022-11-13

## New features and enhancements

* mkvmerge: AV1 parser: the variable-width OBU size field will be re-written

with minimal length if it's encoded longer than necessary.

* mkvmerge: when splitting is active the program will output the timestamps

actually used for making the decision when to split. If GUI mode is active,

a specially formatted line `#GUI#splitting_before_timestamp timestamp` is

output as well. Lines prefixed with`#GUI#` are suitable for machine parsing,

won't be translated and are guaranteed not to change in format. Implements


* MKVToolNix GUI: multiplexer: when dragging & dropping directories to the

"attachments" tab, the files contained in those directories will be

attached. Implements #3410.

* MKVToolNix GUI: info tool: added information about the file (directory,

size, modification timestamp) at the top of each tab. Implements #3407.

## Bug fixes

* mkvmerge: AV1 parser: fixed the parser completely aborting when parsing the

OBU size field fails due to there not being enough data to parse. Instead

the parser will remember the last known-good position & restart from there

after more data is available. Fixes #3431.

* mkvmerge: HDMV PGS subtitles: reverted the change that implemented a

heuristic for detecting bogus timestamps & attempting to fix them. This was

done to fix #3268. Unfortunately this affected valid subtitle files with

intentional huge gaps in timestamps, e.g. forced subtitle tracks. The

heuristic has simply been removed, fixing #3392.

* mkvmerge: Matroska reader: fixed reading files with EBML Void elements

before the Matroska Segment element.

* mkvmerge: fixed reversed attachment selection: `--attachments !4` would not

copy any attachment instead of all attachments but the one with ID 4. Fixes


* mkvextract: IETF BCP 47/RFC 5646 language tags: mkvextract will now use &

prefer IETF BCP 47 track language elements if they're present. Only affects

the VobSub & USF subtitle extraction.

* mkvpropedit, MKVToolNix GUI's chapter & header editors: updated the list of

deprecated Matroska elements. The applications will no longer try to write

those elements, even if they're found in the file to be modified. The

programs will no longer abort with error messages such as `assertion "false"

failed`. Fixes #3416.

* mkvpropedit, MKVToolNix GUI's chapter & header editors: when the Matroska

version numbers stored in the EBML Head element are updated, the updated

EBML Head element might be smaller than the existing one. In that case the

programs used to shrink the EBML Head & write a small EBML Void element

between the updated EBML Head & the following element, usually a Matroska

Segment element. This isn't widely supported by programs including

MKVToolNix itself, causing them to declare such files as invalid. The

programs will now create the EBML Void element inside the EBML Head element,

making them a level 1 element instead of a level 0 element. Fixes #3355.

* mkvpropedit, MKVToolNix GUI's chapter & header editors: often the programs

have to relocate the Master elements in which the modifications were

done. In that case the Seek Head elements must also be updated to reflect to

the Master elements' new positions. If a file contained a Seek Head element

at the start already and if that Seek Head was too small to contain the

updated positions, the programs would end up in an endless loop trying to

write data to the end, creating ever-growing files. This is now handled

properly by voiding this too-small Seek Head & finding a proper space for a

new one instead. Fixes #3338.

* MKVToolNix GUI: header editor: fixed pixelated icons on higher display

scaling values. Fixes #3420.


Download MKVToolNix a small collection of tools (mkvmerge, mkvinfo, mkvextract, mkvpropedit and mmg) that allows you to manipulate Matroska (MKV) files in several ways.

You can use MKVToolNix to create, split, edit, mux, demux, merge, extract or inspect Matroska files. The program will also work with other video formats (AVI, MPEG, MP4, MPEG, Ogg/OGM, RealVideo, MPEG1/2, h264/AVC, Dirac, VC1) including some video codecs (such as VP9 video codec support - reading from IVF/Matroska/WebM files, extract to IVF files). Audio formats (AAC, FLAC, MP2, MP3, (E)AC3, DTS/DTS-HD, Vorbis, RealAudio) and also most subtitle formats (SRT, PGS/SUP, VobSub, ASS, SSA, etc.). MKVToolNix is a cross-platform application that will work on Windows® (both 32 and 64-bit versions), Mac® OS X® and Linux. Please note that from this page you can download the Windows® (installer and portable) and Mac® OS X® versions. If you're looking for a Linux version, you can download one from MKVToolNix homepage.

Trademark Note 1: Microsoft®, Windows® and other product names are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries.

Trademark Note 2: Mac and OS X are trademarks of Apple Inc., registered in the U.S. and other countries.

MKVToolNix Review

Note: I tested MKVToolNix on Windows® 7 Ultimate 32-bit using mkvmerge GUI and several other tools opened from the Command Prompt such as mkvinfo. Therefore, if you're looking for more information on how to compile MKVToolNix yourself, check the README file (online). I wanted to test two things: the mkvmerge GUI (software interface) and see how easy or hard is to use the command line for all the other tools such as "mkvinfo."

The software interface (mkvmerge GUI)

As soon as the setup finished, I opened the "mkvmerge GUI" shortcut from my desktop. At a first look, the interface seems quite intuitive, so my first action was to open an MKV file, select an option and see the result. I went to program interface at the "Input" tab and used the "Add" button (it also works using the "drag and drop" method. 

I selected a 710 MB MKV file and I wanted to split this (from "Global" tab - select "Split Mode" - "split after size" and then I specified the size - in this case 50M = 50MB) in smaller files with a size of 50 MB for each. Finally, I clicked on "Start Muxing" button. 

The program required just 45 seconds for this operation, and the result was 14 smaller MKV files. After this, I wanted to mux the content of an AVI file in MKV format. Again, I went to "Input" tab and used the "Add" button, I selected an AVI file from my computer, and I noticed that the program displayed the Output filename automatically with the name of the same file but this time in MKV (Matroska) format. 

Again, the same button called "Start Muxing" was doing all the magic. This time the process was even faster - at the end I could read the following message "Muxing took 34 seconds".

Other command line tools (example: mkvinfo)

To use all the other command line tools in Windows®, open a Command Prompt window. Just hit the "Start" button, click on "Search programs and files" (Windows® 7 and Vista) or "Run" (Windows® XP and others) and type either "cmd" or "command prompt" (without the quotes). 

In the command prompt, you can try each program (mkvmerge, mkvinfo, mkvextract, mkvpropedit) by typing its name and the usage parameters. An example would be: "mkvinfo --help" that will display a list with all the commands available. I tried mkvinfo using this command: "mkvinfo -g" and the result was a small interface that allowed me to open an MKV file and see all kind of technical details about it. I was also able to save the results in the TXT format.


You can launch an instance of mkvmerge GUI (software interface) directly from the command prompt. Just type "mmg" and hit "Enter."

Besides of the usual standard documentation from the command prompt (I hate it because it's hard to read) you can find and read the online documentation available on MKVToolNix documentation homepage here: (use the blue links for mkvmerge, mkvinfo, mkvextract, mkvpropedit and mmg to access the online help).

Final Conclusion

You can learn how to use several main features in minutes but to master the program, it does require more time. Your best bet is to experiment all of his options and whenever you need some help, check the FAQ section (filled with great answers to common issues), start with the guide of mkvmerge GUI here and check the documentation for all the other tools - here (provided once again). MKVToolNix is a "must-have" software if you work with MKV files. It has an incredible amount of features that are not listed on the homepage. Ultimately, if you appreciate this tool, please consider a DONATION to support the work of Mr. Moritz Bunkus, the author of MKVToolNix.

Found this software useful? Please consider a donation to the author.