Convert WebM to MP4
Turn a WebM into an H.264 MP4 that plays on essentially everything.
Drop a clip to start
Runs in your browser. Nothing is uploaded.
WebM is what a browser produces. Record your screen with a web tool, save a video from a site, export from something built on web technology, and a .webm is what lands in your downloads — at which point it stops being convenient, because outside a browser rather a lot of things will not open it.
MP4 with H.264 is the format nothing refuses. Phones, TVs, editors, presentation software, messaging apps and hardware from the last fifteen years all take it, and that reach is the entire reason for this conversion.
The audio is converted too, since an MP4 will not hold Opus in the way most players expect — it becomes AAC. Both are lossy, so this is a second compression pass on the sound as well as the picture; keep the quality high if the WebM is the only copy you have.
Step by step
- 1Drop in your WebM files.
- 2Pick a resolution and quality.
- 3Press Convert, then download.
Questions
Why will nothing open my WebM?
It is a web format. Browsers all support it, but a lot of desktop software, phones and TVs never added it. MP4 is the one that plays everywhere.
Will the file get bigger?
Usually a little, at matched quality, because H.264 needs more bits than VP9 to look the same. That is the cost of the compatibility.
Does the quality drop?
It is a second lossy pass, so slightly. At high quality the difference is very hard to see.