WebM is the open, royalty-free video format of the web. It plays in every current browser and is a good fit for video on your own site.
The video is encoded to VP9 (or VP8 if your browser can’t make VP9) and the sound to Opus. This re-encodes the video, so it takes about as long as the clip plays. The video never leaves your device. It is read and saved by your browser, so there is no upload, no queue and no copy on a server.
How to convert MP4 to WebM
- Drop your MP4 file on the box above.
- WebM is already selected. You can pick another format if you need one.
- Press Convert to WebM and download the new file.
Questions
Is WebM smaller than MP4?
VP9 is often a little smaller than H.264 at the same quality.
Will it play on iPhone?
Current iPhones play WebM in Safari, but MP4 is still the safest file for sharing.
Does it keep transparency?
No, the output has no alpha channel.