MP4 to WebM converter
To convert MP4 to WebM, drop your MP4 file in the box below. It converts straight away; press Download to save the WebM. It all happens in your browser, so your file stays on your device.
Convert to
What changes
| MP4 to WebM | What happens |
|---|---|
| Picture | Re-encoded as VP9 (VP8 where the browser has no VP9 encoder) |
| Sound | Re-encoded as Opus |
| Size | Same as the original, 1080p, 720p or 480p (never larger) |
| Quality | Smaller file, balanced or best |
| Where it happens | In your browser; the file is never uploaded |
How to convert MP4 to WebM
- Add your MP4. Drop the file in the box, or click to choose it. It becomes WebM straight away.
- Check the result. Look at the preview and the size. The defaults are right for most files.
- Download. Press Download to save the WebM.
WebM is the open web video format: small files that play in every browser and in HTML5 video tags without licence worries.
Questions
Chrome, Edge and Firefox encode VP9 or VP8 with Opus sound. If WebM is not in the list, this browser has no encoder for it.
Usually a little, at the same look: VP9 needs about a quarter fewer bits than H.264. Choose “Smaller file” or a lower size for more.
Recent iPhones and Macs play WebM in Safari, but many other apps do not. Keep the MP4 for sharing with phones.
No. The conversion happens right in your browser, so your file stays on your device. There is no account to make, either.