Video guide
How to remux MKV to MP4 without re-encoding
Remuxing changes the container around existing audio and video streams. When the streams are supported by the target container, this is fast and avoids another encode.
What remuxing changes
An MKV or MP4 file is a container that holds video, audio, subtitles, and metadata. Remuxing copies selected streams into a different container; it does not convert the codecs. That means the encoded audio and video remain unchanged.
Check compatibility
MP4 and MKV support different sets of codecs and features. For example, an H.264 video stream is commonly used in MP4, while some subtitle formats or audio codecs may not be accepted by a target container or playback device. A successful remux does not guarantee every player can open every stream.
Remux a video
- Open Mytory Video Tools and choose Remuxer.
- Load your file and select MP4, MKV, or MOV as the output container.
- Save, then test playback in the app or device you plan to use.
Mytory Video Tools is a free Electron desktop app with FFmpeg included. It runs locally on Windows, macOS, and Linux, with no command line required.