Convert MKV to MP4
Free, no watermark, no signup, and your file never leaves your device.
MKV (Matroska) is a container beloved by archivists, it holds anything: multiple audio tracks, subtitles, chapters. That flexibility is exactly why phones, smart TVs, and editing apps often refuse it; supporting everything MKV can contain is hard, so many devices don't try.
Since the video inside an MKV is very often already H.264, conversion is frequently just a rewrap into MP4, fast and lossless. When the codec inside isn't MP4-compatible, the tool re-encodes it. Either way, processing is local to your browser; a multi-gigabyte file never has to crawl through an upload.
Note: MP4 carries one audio track and no soft subtitles from the source, the primary audio track is kept. If you need a specific track from a multi-track MKV, that's a planned option.
Questions people ask
- Will conversion keep the original quality?
- When the MKV contains H.264 video, yes, the video stream can be copied into the MP4 unchanged. Other codecs are re-encoded once at high quality.
- What happens to subtitles and extra audio tracks?
- MP4 output keeps the primary video and audio track. Embedded subtitle tracks aren't carried over, extract them separately if you need them.
- Why won't my TV play MKV over USB?
- Many TVs support the codecs inside but not the Matroska container, or only partially. MP4 is the container every TV firmware is tested against.