Convert MKV videos to MP4 that plays everywhere, free, no upload.
Open Video ConverterMKV (Matroska) is a flexible container popular for movies and multi-track video, but many phones, browsers, editors and upload forms do not accept it. Since MKV often holds H.264 video, converting to MP4 is frequently a quick rewrap that keeps the original quality while making the file universally playable.
When the MKV contains H.264, omnikitbolt copies the stream into MP4 with no quality loss. If the codec is incompatible with MP4, it transcodes to H.264 at a high-quality setting.
| Format | File Size | Quality | Compatibility | Use Case |
|---|---|---|---|---|
| MP4 | Small to Medium | High (H.264) | Universal | Sharing everywhere, web, social |
| MKV | Medium | High | Players, media servers | Movies, multi-track archives |
| MOV | Medium | High | Apple-centric | iPhone capture, editing |
| WebM | Small | High (VP9) | Modern browsers | Web embedding |
Open the MKV to MP4 converter
Click the button above or go directly to /tools/convert-video. No signup required- the tool is free and works instantly in your browser.
Drop your files
Drag and drop your MKV files onto the upload area, or click to browse. You can convert up to 20 files at once on the free plan (500 on Pro).
Download your MP4 files
Click Download on each file or use Download All as ZIP to save everything at once. All processing happens in your browser- nothing is uploaded to a server.
Complete privacy
Your files never leave your device. All conversion happens inside your browser using the Canvas API and WebAssembly.
Instant results
No upload, no queue, no waiting for a server. Conversion starts the moment you drop your files.
True batch processing
Convert up to 20 files at once on free (500 on Pro) and download them all as a ZIP. No signup required.
Always free
Core conversion tools are free forever. No watermarks, no file size caps on common formats, no account required.
Does MKV to MP4 reduce quality?
Not when the MKV already uses H.264, because the stream is copied into MP4 unchanged. A re-encode only happens for codecs MP4 cannot hold, and then a high-quality setting is used.
Why won't my MKV play?
MKV is a flexible but less universally supported container. Many phones, browsers and editors expect MP4. Converting fixes playback while keeping the video intact.
Is the conversion private?
Yes. It runs entirely in your browser with WebCodecs. Your MKV is never uploaded to a server.
Ready to convert? It takes less than 10 seconds.
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