Convert MKV to MP4 Online

Upload an MKV file and convert it to widely compatible MP4 format. Plays on any phone, tablet, smart TV, or computer.

How it works

  1. Upload your MKV file. Drag your MKV video into DomeScribe. Matroska files with multiple video, audio, and subtitle tracks are fully supported — even those with complex chapter structures.
  2. Select tracks to include. DomeScribe lists every stream in the MKV container. Pick which audio track and subtitle track to carry over to the MP4 output, or keep the defaults for a quick conversion.
  3. Configure MP4 encoding. Choose your video codec and quality. If the MKV already uses H.264, DomeScribe can remux without re-encoding for a near-instant, lossless conversion. Otherwise, select H.264 or H.265 and set your preferred quality level.
  4. Convert and download. Click Convert to repackage or transcode your MKV into MP4. The output plays on smart TVs, game consoles, tablets, and any modern media player without needing third-party codec packs.

Converter at a glance

Video formats
MP4, WebM, MOV, AVI, MKV
Audio formats
MP3, WAV, FLAC, M4A, OGG, AAC
Privacy
Runs 100% in your browser (WebAssembly) — your file is never uploaded to a server
Speed
No upload or download wait — conversion starts instantly, even for large files
Watermark
None, ever
Free tier
10 conversions per month

Frequently asked questions

Why do some devices not play MKV files?

The Matroska (MKV) container is highly flexible but not widely supported by consumer electronics. Most smart TVs, game consoles, and mobile devices are optimized for MP4. A DomeScribe conversion to MP4 ensures playback works on all these devices without installing extra apps.

Can DomeScribe convert MKV to MP4 without re-encoding the video?

Yes, if your MKV contains H.264 or H.265 video with AAC audio, DomeScribe can remux the file — simply repackaging the existing streams into an MP4 container. This is nearly instant and completely lossless.

What happens to subtitles in my MKV file during conversion?

MKV files often contain soft subtitles (SRT or ASS format). DomeScribe can embed these as a subtitle track in the MP4 or burn them into the video. Subtitle handling options are shown during the conversion setup.

Will chapter markers from my MKV transfer to the MP4?

MP4 supports chapter metadata, and DomeScribe preserves chapter markers when they are present in the source MKV. This is especially useful for long-form content like movies or audiobooks where chapters aid navigation.

My MKV has DTS or Dolby audio — will that work in MP4?

MP4 natively supports AAC audio but not DTS or many Dolby formats. DomeScribe will transcode the audio track to AAC, which is universally supported while still delivering high-quality surround or stereo sound. The video stream can often be remuxed without re-encoding.

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