MP4 to WebM
An MP4 is what everything writes and everything plays
…
- 1
Where your MP4 came from
An MP4 is what everything writes and everything plays. If you are converting away from one, it is because something specific wants a different box.
- 2
Why you are converting it
A web page you control. WebM at VP9 is meaningfully smaller than the same picture as H.264, and every current browser plays it, which is the only place that trade pays off.
- 3
The thing that decides the wait
Real time and a little quality. H.264 cannot go into a WebM, so every frame is decoded and encoded again, which takes about as long as the video is. This is the slow direction and the page says so before you start.
FAQ
- How do I convert MP4 to WebM?
- Drop the file on this page and press the button. It runs in your browser, so there is no upload, no account and no daily limit.
- Why will my software not open a MP4 file?
- Nothing refuses an MP4. What wants something else is usually an Apple editing workflow asking for MOV, or a web page that would rather serve a smaller WebM.
- Is there anything odd about MP4?
- Going out of MP4 is the one direction where compatibility gets worse on purpose, in exchange for something else: a smaller file, or a container a particular editor prefers.
- Why WebM specifically?
- Real time and a little quality. H.264 cannot go into a WebM, so every frame is decoded and encoded again, which takes about as long as the video is. This is the slow direction and the page says so before you start.
- Is the file uploaded?
- No. The video is opened and written back out in the page. No request carries it anywhere, which the network panel will show you while it runs.