No, conversion happens locally in your browser.

MKV to MP4

Convert MKV videos to universally-compatible MP4.

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About MKV to MP4

Turn MKV files into MP4 (H.264) that plays on virtually any device or platform. Runs entirely in your browser, no uploads.

Open the MKV to MP4 tool and add your file. It's processed in your browser, never uploaded.
Adjust the available options to get the result you want.
Download the result. There's no sign-up, no watermark, and no size cap.

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