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Convert.mkv

Convert MKV to MP4 online

100% localFiles never leave your device — no upload, no account, no tracking.
About MKV to MP4

Convert MKV (Matroska) videos into MP4 so they play on devices and apps that don't support the MKV container. We re-encode to H.264 with ffmpeg.wasm at the quality you choose.

The transcode runs entirely in your browser. Your MKV file never leaves your device.

How it works
  1. 01

    Add an MKV

    Drop your MKV file onto the page or pick it from your device.

  2. 02

    Set quality

    Choose a CRF value for the output quality.

  3. 03

    Convert

    Click Convert to encode an MP4 locally with ffmpeg.wasm.

  4. 04

    Download

    Save the MP4 file.

Features
H.264 outputbroad compatibilityadjustable quality
Frequently asked
How does the MKV to MP4 converter work?
Convert MKV (Matroska) videos into MP4 so they play on devices and apps that don't support the MKV container. We re-encode to H.264 with ffmpeg.wasm at the quality you choose.
Are my files uploaded to a server?
No. Everything runs entirely in your browser using local JavaScript and WebAssembly. Your files never leave your device.
Does it cost anything or require an account?
No. The converter is free, needs no sign-up, and runs locally in your browser.
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