MKV to MP4 Converter
Convert MKV video files to MP4 format online. Free, fast, and private.
Upload your MKV files and convert them to universally compatible MP4. MKV (Matroska) is popular for high-quality video with multiple audio and subtitle tracks, but many phones, TVs, and media players cannot play MKV files directly. MP4 works on every device and platform. All conversion happens in your browser using WebAssembly. Your videos never leave your device. Need a different conversion? Try MOV to MP4 or our video compressor.
Drop MKV files here
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Supports: Matroska MKV video files
How It Works
- 1Upload MKV files
Click or drag and drop your .mkv video files. MKV files are commonly used for movies, TV shows, and high-quality video content.
- 2Choose quality settings
Select output quality and resolution. High quality with original resolution preserves the video as close to the original as possible.
- 3Convert and download
Click Convert to MP4 and download your files. Preview the converted video before saving. Need to trim it? Use the Video Trimmer.
Frequently Asked Questions
Why convert MKV to MP4?
MKV (Matroska) is a flexible container format popular for movies and TV shows because it supports multiple audio tracks and subtitles. However, many smartphones, smart TVs, gaming consoles, and social media platforms cannot play MKV files. MP4 is universally supported on all devices and platforms.
Will I lose subtitles when converting?
MKV files often contain embedded subtitles. During conversion to MP4, soft subtitles (text-based) may not carry over since MP4 has limited subtitle support compared to MKV. If your MKV has burned-in (hardcoded) subtitles, those will be preserved since they are part of the video stream. See our MKV vs MP4 comparison.
What about multiple audio tracks?
MKV files can contain multiple audio tracks (different languages). The converter uses the first/default audio track. If you need a specific audio track, you may want to use desktop software like HandBrake for more control.
Are my videos uploaded to a server?
No. All conversion runs in your browser using FFmpeg WebAssembly. Your videos never leave your device. No data is uploaded, stored, or tracked. See our security page.
Is there a file size limit?
Since processing happens in your browser, the limit depends on your device memory. Most devices can handle files up to 500MB-1GB. For very large MKV files (2GB+), your browser may run out of memory. If you need to reduce file size afterward, use our video compressor.
Is this converter free?
Yes. This MKV to MP4 converter is completely free with no file limits, no signup, and no watermarks. Convert as many videos as you need. You can also convert videos to GIF or extract audio from your videos.