Is it safe to convert MP4 to WebM here?

Yes — your .mp4 file is converted entirely on your device. It is never uploaded anywhere.

Will the converted .webm file lose quality?

We use ffmpeg's standard settings for this pair, matching quality you'd get from a desktop tool.

Is there a file size limit?

Files up to 500MB are supported. No account required.

Convert MP4 to WebM

Convert MP4 to WebM for smaller, web-optimized video files.

Drop a .mp4 file or click to browse

Max file size 500MB • No Account Required • Files Never Touch a Server

File signature verified before conversion — never uploaded

About converting MP4 to WebM

MP4 (.mp4) files can be converted to WebM entirely in your browser — no software to install, no file upload, and no account required. The conversion runs on a WebAssembly build of ffmpeg directly on your device.

FAQ

Is it safe to convert MP4 to WebM here?: Yes — your .mp4 file is converted entirely on your device. It is never uploaded anywhere.
Will the converted .webm file lose quality?: We use ffmpeg's standard settings for this pair, matching quality you'd get from a desktop tool.
Is there a file size limit?: Files up to 500MB are supported. No account required.

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