MKVtoolnix is a set of tools to create, alter, and inspect Matroska files under OS X, Linux and other Unices, and Windows. They do for Matroska what the OGMtools do for the OGM format and then some.

Since May 1st 2003, the Matroska libraries themselves and my Matroska tools are officially released as a first public beta version. Although all of them are still under heavy development, I urge you to download the software, test it and report any errors you encounter to me. I’m always grateful for good bug reports because I miss so many mistakes and you guys normally find them. Your feedback is important to me

What’s New in MKVToolNix 40.0.0

New features and enhancements

• Mkvmerge: MP4 reader: added support for BMP covert art images.
• MKVToolNix GUI: multiplexer: added an option to disable deriving the destination file name from the file title. Implements #2648.
• MKVToolNix GUI: multiplexer: the content of the “stereoscopy” combo box has been simplified making the box’s minimum width much smaller, allowing the user to resize the GUI’s whole window to a much smaller width.
• MKVToolNix GUI: multiplexer: whenever the user changes the “aspect ratio” or “display dimensions” controls, the corresponding radio button will be activated automatically. Implements #2651.
• MKVToolNix GUI: Windows: added a setting in the preferences to disable the GUI’s dark color mode even if Windows’s app color mode is set to dark. Implements #2646.
• MKVToolNix GUI: Windows: replaced the dark mode introduced in v39 with another dark mode that’s less wasteful with space between widgets.

Screenshots