MKV TO MP4 AND MORE
Convert MKV to MP4, or any other video format.
The most common job here is MKV to MP4, and it usually finishes in seconds. The same tool also handles MOV, WEBM, AVI and animated GIF, and can pull the audio out on its own as MP3 or WAV. Nothing is uploaded, the conversion runs on your own device.
Drop a video here, or browse
MKV, MP4, MOV, AVI, WEBM and more. Nothing is uploaded
When the video already uses a format the target container accepts, it is repackaged rather than re encoded and finishes in seconds.
Getting ready
Frequently asked questions
Drop the MKV file on the tool, pick MP4 as the target, press convert. Most MKV files already hold video that MP4 is happy to accept, so the file gets repackaged rather than rebuilt from scratch, done in seconds with zero quality lost.
No. The whole thing runs inside your browser, on your own device. Nothing gets sent anywhere, which is rare for a video converter and is exactly why there is no file size charge and no queue to wait in.
Because a browser tab is doing a job a desktop program would do with far more access to your machine. Repackaging is fast. Rebuilding a long video from scratch takes real time, sometimes longer than the video itself runs. Short clips are where this tool feels at home.
The converter is a full video engine and it has to download before anything can happen. It is a big file. Once it has loaded once, it stays cached, so the next conversion in the same session starts right away.
Whatever your browser can spare the memory for. A clip of a few hundred megabytes is comfortable on a normal computer. Push past that and the tab can run out of memory, and there is genuinely no workaround for that from inside a browser.
Yes. Pick MP3 or WAV as the format and only the audio track gets written out, which is a lot faster than a full video conversion.
Repackaging never touches the video, so quality stays exactly as it was. Rebuilding it always costs a little, and the quality setting decides how much. High keeps more detail in a bigger file. Small does the opposite.
An MKV to MP4 converter that keeps the file on your computer
Almost every free video converter online works the same way. You upload the video, it gets converted somewhere else, and you are asked to trust that the copy was deleted afterward. Fine for a throwaway phone clip. Not fine for anything personal, or anything that belongs to a client, since that means handing a private file to a company you know nothing about and waiting on an upload before the actual work even starts.
My honest take, having built this the other way round: doing the conversion on your own machine is simply the better default. No upload, no queue, no account, and the only real limit is your own hardware rather than whatever a free tier decided to allow you.
MKV to MP4 is usually instant
A video file is really two things stacked together. There is the container, the outer wrapper, and that is what MKV, MP4, MOV and AVI actually name. Then there is the video itself sitting inside, usually encoded as something called H.264.
Most MKV files already hold H.264 video, and MP4 is perfectly happy to accept H.264. So converting one to the other is often nothing more than moving the same footage into a different wrapper. The tool checks for that first and takes the shortcut whenever it can, which finishes in seconds and loses no quality, because the video itself is never touched. Only when the two formats genuinely disagree does it fall back to a real conversion.
What it is good at, and what it is not
Being clear about this saves you a wasted hour.
It suits changing containers, short clips, phone videos, screen recordings, pulling audio out of a video, and making a GIF from a few seconds of footage.
It does not suit long films, large archives, or batch work across dozens of files. A browser tab has a memory ceiling and a speed penalty, and no amount of clever code removes either. If you convert big videos regularly, a desktop program is the right tool and this is not trying to replace it.
Formats
Video can go out as MP4, MKV, MOV, WEBM or AVI, or as an animated GIF. Audio can be pulled out on its own as MP3 or WAV. Most common formats are accepted going in, including MKV, MP4, MOV, AVI, WEBM, FLV, WMV and MPEG.
Once you have the file, the photo to PDF converter and the image converter handle the still image side of things if you need it.
For a walkthrough with a real example, see the blog guide on converting MKV files to MP4 for free, or the shorter how to convert MKV to MP4 guide.