Convert a tweet to WebM
WebM is the right choice when the video is going onto a web page. A ten-second WebM is routinely a tenth the size of the equivalent GIF at visibly better quality, which is why an autoplaying muted WebM has replaced the GIF on most modern sites.
It is also the universal fallback here: browsers without WebCodecs cannot produce MP4, but almost all of them can record WebM from a canvas. If you choose MP4 on an older Safari, this is what you get, and the tool tells you rather than mislabelling the file.
Questions
- Should I use WebM or MP4 on my website?
- Serve both if you can, WebM first. WebM is smaller; MP4 covers the handful of players that still refuse WebM.
- Why does WebM export take as long as the video is?
- WebM here is recorded from the canvas in real time rather than encoded frame by frame, so a six-second clip takes about six seconds. MP4 encodes faster than real time.
- Can I upload WebM to Instagram or TikTok?
- Not reliably. Both prefer MP4. Use WebM for websites and MP4 for social platforms.