MKV to MP4
Turn MKV videos into MP4 files that play on phones, TVs, iMovie and every video site.
or drop it here · up to 50 MB, free
Bigger files? Pro converts files up to 500 MBOver the free limits: you can unlock the download from €1.99.
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Free · No sign-up · No watermark · Your files never leave your device
MKV to MP4 in 3 steps
- Select your MKV video, or drop it on the box.
- Keep Fast, or choose Most compatible for old players.
- Click Convert to MP4 and download the file.
From MKV to MP4, the quick way when possible
MKV (Matroska) is a flexible container popular with screen recorders such as OBS and for films, but iPhones, iMovie, PowerPoint and many TVs do not open it. When the video inside is H.264 or HEVC, Fast mode moves it into an MP4 file without re-encoding, so the conversion takes seconds and the quality stays exactly the same.
Other video codecs, such as VP9 or AV1, are re-encoded as H.264, and sound in formats MP4 players do not handle well becomes AAC (Opus in Firefox, which cannot create AAC). MP4 holds one video and one sound track in this tool, so extra audio languages and subtitle tracks in the MKV are left out; the main video and its default sound track are kept.
Frequently asked questions
How do I convert MKV to MP4 for free?
Select the MKV file and click Convert to MP4. Files with H.264 video, which includes most OBS recordings, are ready in seconds. Others are re-encoded, which takes about as long as the video. The MP4 downloads straight away, with no watermark.
Does converting MKV to MP4 lose quality?
Not when the video can be copied: the page tells you the original streams were kept. When it has to be re-encoded, it is done at high quality and the same resolution, and the difference is very hard to see.
What happens to subtitles and extra audio tracks?
The MP4 gets the main video and the default sound track. Additional languages and subtitle tracks are not copied. If you need them, keep the MKV as well, or burn the subtitles in with a desktop video editor.
Why convert OBS recordings from MKV to MP4?
OBS recommends MKV because a crash cannot corrupt the whole file, but editors and upload sites prefer MP4. Converting in Fast mode turns the recording into an MP4 in seconds without touching the picture.
Which browsers can do this?
Fast mode only needs a recent browser. Re-encoding uses the video encoder built into it. Chrome and Edge on a computer or Android phone work best. Safari 17 or later and recent Firefox versions also work, but they are slower with large videos. If your browser cannot do it, the page tells you before you start.
Is my video uploaded to a server?
No. The video is processed by your own browser on your device, so it is never sent to us or stored anywhere. That also means there is no upload to wait for, which saves a lot of time with large videos.