Convert MP4 to WEBM
Convert MP4 to WEBM free in your browser. No upload, no signup, no watermark. Files stay on your device.
drop a .mp4 file
or click to browse
max 500 MBrelated
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how to convert mp4 to webm
Add your MP4 file
Drag and drop your MP4 file into the drop zone above, or click the box to browse for a file.
Click Convert
The conversion happens locally in your browser. No upload, no server, no waiting in queue.
Download the WEBM file
When the conversion finishes, the WEBM file is ready to download. Save it anywhere on your device.
FAQ
common questions
Is the MP4 to WEBM converter free?
Yes. Every conversion on this site is free, with no signup, watermark or file count limit.
Are my files uploaded to a server?
No. Conversion runs entirely in your browser using ffmpeg.wasm. Your files never leave your device, so we cannot see them even if we wanted to.
Is there a file size limit for MP4 to WEBM?
Files up to about 500 MB work reliably. Larger files may run out of memory depending on your device.
Does it work offline?
Once this page has loaded, yes. You can disconnect from the internet and the converter will still work. Reloading the page does require connectivity.
Will my MP4 file lose quality when converted to WEBM?
It depends on the formats involved. Converting between lossy formats (JPG, MP3) re-encodes data and slightly reduces quality. Lossless formats (PNG, WAV, FLAC) preserve everything. Pixel dimensions and color depth are preserved for image conversions.