No, conversion happens locally in your browser.

WebM to MP4

Convert WebM videos to universally-compatible MP4.

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About WebM to MP4

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

Open the WebM 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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