MP4 to WebM

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

Choose a file or drag & drop

How to use MP4 to WebM

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

Private MP4 to WebM conversion

WebM is an open, royalty-free format ideal for HTML5 video on the open web.

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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