File Converter

MKV to MP4 converter Free, private, no upload.

Convert MKV files to MP4 right in your browser. MP4 plays on every phone, browser, TV, social network and video editor. Your files are never uploaded.

or drop files anywhere · paste with Ctrl/⌘ + V

How to convert MKV to MP4

  1. 1 Drop your MKV files onto the page, or click “Choose files”. You can add many at once, or a whole folder.
  2. 2 MP4 is already selected as the output. Optionally open Options to adjust quality, resolution, frame rate.
  3. 3 Click Convert, then Save. Converting several files? Save them all as one ZIP.

About the formats

MKV · Matroska video

MKV is a flexible open container that can hold many video, audio and subtitle tracks. It is common for films and screen recordings (OBS).

MP4 · MPEG-4 video

MP4 is the most widely supported video format, typically H.264 video with AAC audio.

The conversion runs on your device using FFmpeg compiled to WebAssembly. You can adjust: quality, resolution, frame rate, encoder speed, remove audio, start at, end at.

Frequently asked questions

How do I convert MKV to MP4?

Drop your MKV files onto the page, or click “Choose files”. You can add many at once, or a whole folder. MP4 is already selected as the output. Optionally open Options to adjust quality, resolution, frame rate. Click Convert, then Save. Converting several files? Save them all as one ZIP.

Are my files uploaded to a server?

No. The conversion runs entirely in your browser using WebAssembly. Your files never leave your device, so it is safe for private photos, contracts and business data. Once the page has loaded it even works offline.

Will converting MKV to MP4 reduce quality?

MP4 uses lossy compression, so some detail is traded for a smaller file. At the default quality the difference is very hard to see or hear, and you can raise the quality setting if you need more.

Can I convert multiple MKV files to MP4 at once?

Yes. Add as many MKV files as you like; they are converted in parallel on your device and you can download them all as a single ZIP.

Is it free? Are there limits?

It is free, with no sign-up, no watermark and no daily limits. Because nothing is uploaded there is no upload size limit either; the only limit is your device’s memory, which matters mostly for very large videos.

Convert other formats to MP4

See everything the MKV converter and the MP4 converter can do.