Download MKVToolNix for Windows PC v103.0 for Windows PC
MKVToolNix is the standard open source toolset by Moritz Bunkus for creating and editing Matroska MKV and WebM files.
Technical Specifications & System Requirements
Software notes
Features
- Remuxing is lossless and fast because MKVToolNix copies existing video, audio, and subtitle streams into a new MKV without re-encoding, preserving original quality while reorganizing tracks exactly how you want them.
- Track-level control is excellent, letting you add or remove subtitle and audio tracks, set language tags, mark default and forced tracks, and name streams clearly for media players and servers.
- The package combines the MKVToolNix GUI with mkvmerge, mkvinfo, mkvextract, and mkvpropedit, so both point-and-click users and script writers can inspect, extract, and batch-process files with the same trusted tools.
- Splitting files by size, duration, or chapters and appending compatible files are built in, which helps archive long recordings, combine multi-part releases, and prepare files for different storage media.
- Input support covers MP4, AVI, WebM, and many subtitle and audio formats, so you can standardize a mixed collection into consistent MKV files that Plex, Kodi, and VLC handle predictably.
Considerations
- MKVToolNix does not re-encode or convert video, so it cannot shrink a file by lowering quality, change codecs, or repair a badly encoded source that needs actual transcoding work.
- The interface exposes many technical options for tracks, attachments, tags, and chapters at once, which can overwhelm beginners who only wanted to add one subtitle file quickly.
- Appending and merging only work cleanly when source files use compatible codecs and parameters, and mismatched files can produce playback problems that are not always obvious during the muxing step.
About & Overview: MKVToolNix for Windows PC
MKVToolNix is the standard open source toolset by Moritz Bunkus for creating and editing Matroska MKV and WebM files. It bundles mkvmerge, mkvinfo, mkvextract, mkvpropedit and a full graphical interface for remuxing video, audio and subtitle tracks without re-encoding. You can add or remove subtitle and audio tracks, split and append files, and edit chapters and headers, with input support for MP4, AVI and many other formats.
How to Install & Verify MKVToolNix for Windows PC
Download MKVToolNix from the official vendor link on this page.
Open the downloaded installer file and follow the on-screen installation steps.
Start MKVToolNix from the Start menu or desktop shortcut.
Related Windows PC Software & Alternatives
Frequently Asked Questions & Verification Guide
Does MKVToolNix reduce video quality?
No, when remuxing MKVToolNix copies the existing streams without re-encoding, so quality is unchanged. It rearranges video, audio, and subtitles into a new container rather than compressing them again.
Can MKVToolNix convert MP4 to MKV?
Yes, you can add an MP4 file in the GUI and mux it into an MKV file. This is a container change without re-encoding, so it is fast and lossless as long as the tracks are compatible.
How do I add subtitles with MKVToolNix?
Add your video file and the subtitle file, such as an SRT, in the multiplexer, set the subtitle language and default or forced flags if needed, then start multiplexing to create a new MKV.
Is MKVToolNix free?
Yes, MKVToolNix is free and open source under GPLv2 and is developed by Moritz Bunkus. You can use it for personal and professional media library work without a license fee.
Can MKVToolNix split a large MKV file?
Yes, the GUI includes splitting options by size, duration, timestamps, or chapters. This is useful for storage limits or separating a long recording into parts without re-encoding any of it.