Convert MP4 to MKV
Convert your MP4 video files to MKV directly in your browser.
How to convert video in 3 steps
Choose a MP4 video file.
Click convert to MKV.
Download your MKV video.
Format descriptions
MP4 — MP4 is the most widespread and compatible video container. It supports H.264/HEVC and AAC codecs, making it ideal for streaming, the web and mobile devices.
MKV — MKV (Matroska) is a flexible open-source video container that supports multiple video, audio and subtitle tracks in a single file.
Technical comparison: MP4 vs MKV
Technical breakdown of the MP4 and MKV specifications: compression, colour, transparency and animation support.
| Property | MP4 | MKV |
|---|---|---|
| Specification | MP4 (MPEG-4 Part 14) | MKV (Matroska Multimedia Container) |
| Media type | Video | Video |
| Compression | Lossy · H.264 / HEVC + AAC | Hybrid (lossy or lossless) · H.264 / HEVC / VP9 / AV1 |
| Color space / bit depth | YUV 4:2:0, 8-10 bit | 8/10/12-bit HDR |
| Transparency | Not supported | Not applicable |
| Animation | Yes (animated) | Yes (animated) |
| Best for | MP4 is the most widespread and compatible video container. It supports H.264/HEVC and AAC codecs, making it ideal for streaming, the web and mobile devices. | MKV (Matroska) is a flexible open-source video container that supports multiple video, audio and subtitle tracks in a single file. |
What happens when converting MP4 to MKV?
The MP4 data is decoded inside your browser with WebAssembly and re-encoded to the MKV specification, so no file is ever uploaded to a server. Both formats rely on comparable compression, so file size and perceived quality stay in the same range.
Frequently Asked Questions
What is video conversion?
Video conversion changes a video file from one format to another, for example from MP4 to MKV, while keeping the video content.
Are my video files uploaded?
No. This tool processes video files directly in your browser. Your video files are never sent to a server.
Which video formats are supported?
This tool converts MP4 video files to MKV, all in your browser.
Is it really free and unlimited?
Yes, the tool is completely free and you can convert as many video files as you want, with no limits.
Does it work on mobile too?
Yes, it works on any modern device, including smartphones, tablets and desktop computers.
Which format will the result be in?
The converted file will always be in MKV format, ready to download and use.
About the video converter
Convert MP4 to MKV video online for free. Everything happens in your browser: your files are never uploaded to a server, and you need no downloads or sign-up to get started.
See also:
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- Convert MP4 to WEBMConvert MP4 to WEBM video online for free. Everything happens in your browser: your files are never uploaded to a server, and you need no downloads or sign-up to get started.
- Convert MP4 to AVIConvert MP4 to AVI video online for free. Everything happens in your browser: your files are never uploaded to a server, and you need no downloads or sign-up to get started.
- Convert MKV to MP4Convert MKV to MP4 video online for free. Everything happens in your browser: your files are never uploaded to a server, and you need no downloads or sign-up to get started.