XPRTIX Video
Convert MKV to MP4.
Turn an MKV into an MP4 that plays on iPhone and iPad. Usually the video is copied across, with no loss.
compressMOV → MP4trim & cropvideo → GIFfix for iPhoneXPRTIX Video
Convert MKV to MP4: how it works
MKV and MP4
MKV is a flexible container that iPhone cannot open. When the video inside is H.264 or HEVC, it can go into an MP4 as it is, so converting is quick and the picture is not touched.
Sound that will not play
MKV files often carry AC-3, DTS or FLAC audio, which iPhone plays as silence or not at all. Where that is the case the sound is converted to AAC.
On your device
It all runs in your browser. For formats it cannot read natively, a small converter is downloaded once and kept.
Subtitles and multiple audio tracks
An MKV from a download or a rip often holds several things an MP4 handles differently: more than one audio track, subtitle tracks, chapters and attachments. The MP4 made here keeps the video and one audio track. Subtitles, extra languages and chapters are not carried over.
If you need to keep a subtitle, burn it in with a video editor first, or keep the MKV for desktop players such as VLC that open it without trouble. For an iPhone, a single clean video and audio track is what plays.
Transparency
What leaves your device
No video is uploaded. Everything runs in your browser; a small converter (about 3 MB) is downloaded once, and only for a format the browser cannot read. What is recorded.
Video guides
Related Video jobs
Questions
Asked often
Does the MKV go anywhere?
No. It is read and written in your browser, so the file stays on your device.
Is it a copy or a re-encode?
When the video inside is H.264 or HEVC it is copied across untouched. Other codecs, such as VP9 or old MPEG-4, are encoded again to H.264.
What about subtitles?
Subtitles are not carried over. Only video and audio are in the MP4.
Can it open a long movie file?
Videos up to about 2 GB are accepted. Copying a movie takes a few seconds; re-encoding one takes much longer.
Why is there no sound on iPhone?
The audio is probably AC-3 or DTS. Converting to MP4 here changes it to AAC.
Can I keep multiple audio tracks?
Only the main audio track is kept.