MP4 to MKV Converter: Free, Fast and No Upload
Drop in a MP4 file and get a MKV back. Convert MP4 to MKV when you want to use the video in software or a media server that prefers Matroska files. Everything runs on your own device, so your video is never uploaded.
MP4 plays almost everywhere. WebM suits websites. MOV suits Apple devices.
How to use the MP4 to MKV
- Drop your MP4 file onto the converter.
- Check that MKV is selected as the output format.
- Press Convert to MKV, preview the result and download it.
What is MP4?
MP4 is the most widely supported video format. It plays on phones, computers, TVs, browsers and every social platform. It plays on practically everywhere. It is a lossy format, so a re-encode always trades a little quality for size.
What is MKV?
MKV (Matroska) is a flexible container that can hold several audio tracks and subtitles, which is why downloads and screen recordings often use it. It plays on desktop players such as VLC. Many phones, TVs and social platforms will not accept MKV.
Frequently asked questions
How do I convert MP4 to MKV for free?
Open the converter, drop in your MP4 file, press Convert to MKV and download. It is free with no watermark and no sign up.
Why would I convert MP4 to MKV?
MKV is mainly useful for desktop media players and servers. For sharing on phones and social media, MP4 is the better format.
Is my MP4 file uploaded anywhere?
No. The conversion runs in your browser on your own device, so the file never leaves it.
Does converting reduce quality?
The video is re-encoded at high quality, so for normal viewing the difference is not noticeable. Converting never improves quality beyond the original.