Convert MKV to MP4
Free, no sign-up, and your files never leave your device.
Drop your files here
Choose filesNothing is uploaded: everything happens in your browser
The video is processed by your device: allow a few seconds for a format change, longer for compression.
MKV is common for films and game recordings, but many phones, TVs and editing apps cannot open it. When the video is H.264, the conversion copies the stream into an MP4 without loss. Otherwise it re-encodes it to H.264.
How to convert MKV to MP4
- 1Drop your MKV files in the box, or click to pick them. You can add several at once.
- 2MP4 is already selected. Open the settings if you want to change the quality, the size or the background.
- 3Download each file, or everything at once as a .zip. Nothing was uploaded: the conversion happened on your device.
The formats
MKV
The Matroska format, a very flexible container that can carry several audio tracks and subtitles. It is common for films, but many phones, TVs and editing apps cannot open it.
MP4
The universal video format. In H.264 with AAC audio, it plays on every phone, computer, TV and social network. It is the format to aim for when you do not know where the video will be watched.
Your files stay with you
The conversion runs in your browser, with your device's decoders. No file is uploaded, no copy is kept, and nobody but you sees your photos or videos. You can check it in the Network tab of your browser's developer tools: none of your files goes out.
Frequently asked questions
Are subtitles kept?
Not always: MP4 accepts fewer subtitle formats than MKV. Keep the original MKV file if you need them.
What about audio tracks in several languages?
The audio tracks are kept in the MP4. Players then let you choose the language, as with the MKV.
Is the converter really free?
Yes, with no sign-up, no watermark and no limit on the number of files. The conversion runs on your device and costs us nothing, so there is nothing to charge you for.
Are my files sent anywhere?
No. They are read and converted in your browser, then saved straight to your device. No server receives them.
Is there a maximum size?
The limit is your device's memory. Photos and audio files go through without trouble; for a video of several gigabytes, a computer does better than a phone.
Does it work on a phone?
Yes, on iPhone and Android, in Safari, Chrome or Firefox. For video, an up-to-date browser is needed: it provides the decoders being used.
What next, with AI
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