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Convert MP4, AVI, and other videos to multi-track MKV format while retaining original HD quality.
This tool is currently under development. Please check back later!
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When you need to integrate multi-language audio tracks or subtitles into a single video file, scattered MP4 or AVI files can be difficult to manage. Using Matroska container technology, this tool remuxes various videos into the MKV format. It retains the original encoding while supporting the addition of an unlimited number of audio tracks, subtitles, and chapter markers. As an open container format, MKV can encapsulate H.264/AVC, VP9, and other encoded videos, making it an ideal choice for high-definition movie storage.
Can MKV files be played on mobile phones?
Most modern Android and iOS devices natively support MKV. If you encounter compatibility issues, we recommend using a universal media player like VLC.
Will the converted file size increase?
The remuxing process typically only adds about 3-5% in container overhead, while the audio and video stream data remain their original size. If you choose to keep all original stream data, the final file might be slightly larger than the source file.
We recommend keeping single file conversions under 2GB. Converting commercial videos with DRM protection may fail. MKV remuxing does not support editing already compressed stream data.
For Blu-ray disc conversion needs, we recommend extracting the main video stream first (usually 00002.m2ts) before remuxing, which can reduce the file size by up to 90%. Typical conversion example: Input [movie.mp4 (H.264+AAC)] → Output [movie.mkv (Retains original H.264 video + new DTS audio track + English/Chinese subtitles)].