Step 1: Supply your MKV files using the button above or by haul and lay.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Get your converted MP4 files.
MKV to MP4 Conversion FAQ
Will resolution and frame rate be preserved in the MP4?
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Yes. MKV → MP4 keeps resolution, frame rate, and aspect ratio unchanged by default. To change them, use the Resize or Speed tool on the result.
Is the MKV to MP4 conversion reversible?
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You can convert the MP4 back to MKV on this site. If either format involved is lossy, the round-trip is not bit-perfect even though it is visually or audibly close.
Will the MP4 play on a phone without anything installed?
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That is the whole argument for it. MP4 is what phones record to and what every phone, tablet, console, television and browser built in the last decade decodes in hardware, so a file in it opens on whatever the recipient happens to own. Hardware decoding is the part people underestimate: it is why an hour of video plays on a phone without draining the battery, and why nothing else is a safer choice when you do not know what the file will land on. MP4 is the safest possible delivery target — every phone, browser, console, editor and Smart TV built in the last decade plays it without extra software.
My MKV has several audio tracks — do they all survive into the MP4?
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No. The converter keeps one audio track, the one with the most channels (normally the main mix), and drops the rest; there is no setting to pick a different one. To keep another track, remux the MKV with that track first (VLC or ffmpeg can do this), then convert it. MKV is the archival container of choice because it stores unlimited audio tracks, soft subtitles, chapter markers and cover art in one file. MP4 only supports one widely-honoured subtitle format (mov_text), and multi-track audio is unreliable outside desktop players.
My MKV files came from ripping discs — will they convert cleanly?
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Cleanly, yes, but check what is inside first. A rip usually carries more than the picture — often several audio languages, sometimes a subtitle track or chapter marks — and whether those survive depends entirely on what the MP4 can hold, not on the rip. The other thing to know is that the encode already happened: the ripper chose a bitrate years ago and no conversion can recover detail it discarded, so if the discs are still around, re-ripping beats re-encoding. MKV is Matroska, an open container designed in 2002 with no licensing restrictions and no ceiling on what it can hold.
Will the MP4 play in a browser when the MKV would not?
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Yes, and that is usually the whole reason for the conversion. An MKV embedded in a web page either shows a broken player or forces a download, because browsers ship no decoder for it. MP4 plays inline through the native HTML5 video element with no plugin and no external application.
Both MKV and MP4 are modern containers — which should I actually keep?
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Keep whichever matches where the file is going, because neither is better in the abstract. One of these two is built for playback compatibility and the other for holding everything a file might contain, and they trade against each other exactly along that line. The pragmatic answer for most libraries is to archive in the feature-rich container and export to the compatible one on demand.
Is there a file-size limit when converting MKV to MP4?
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Free conversions have a size limit per file, set by the type of file, and the page tells you when a file is over it. A paid plan removes that limit, so much larger files can be converted.
Can I batch-convert several MKV files to MP4 at once?
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Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
What happens to my MKV files after the conversion?
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Uploaded files are processed on our own conversion servers, nobody looks at them, and they are not shared. The upload and the converted file are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.
Will my MP4 play on phones, tablets, and TVs?
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Yes — MP4 uses modern codecs that play natively on iOS, Android, Smart TVs, game consoles, and every modern browser.
Do I need to install software to convert MKV to MP4?
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No. The converter runs entirely in your browser plus our cloud — no plugin, no install, no admin rights. It works on Windows, macOS, Linux, ChromeOS, iOS, and Android.