WebM to MP4

Convert WebM video files to MP4, entirely in your browser.

Choose a file or drag & drop

How to use WebM to MP4

  1. Choose a WebM file.
  2. Click Convert to MP4 and wait for processing.
  3. Download your new MP4 file.

Private WebM to MP4 conversion

WebM is great for the web but not always supported by editors and phones; MP4 fixes that.

Conversion is powered by FFmpeg compiled to WebAssembly and runs locally. The engine downloads once on first use, then your media is processed on your own device — nothing is uploaded.

Is there a file size limit?
The only limit is your device's memory, since processing happens in your browser rather than on a server.
Are my files uploaded?
No. Everything is processed locally in your browser, so your files never leave your device.

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