Convert video to WebM
Convert video to WebM for free — well suited to web pages, where it is usually smaller than MP4 at the same quality and loads faster. Runs locally in your browser: no upload, no account, no watermark.
Result right hereDrop a video here, or click to choose
MP4 · MOV · MKV · WebM · audio · images · subtitles · ZIP
WebM has two advantages on the web: smaller files at equal quality, and support for transparency, which MP4 lacks. That is why animated backgrounds and transparent overlays on web pages tend to use it.
The trade-off is reach: Safari only added WebM support fairly late, so very old devices cannot play it. The usual answer is to offer both an MP4 and a WebM.
Conversion is local; download as soon as it is done.
FAQ
How much smaller is WebM?
Around twenty to thirty per cent at the same quality, depending on content. The busier the picture, the bigger the gap.
Do all browsers play WebM?
All the current mainstream ones. Safari supports it from version 14; older versions do not. Offer an MP4 alongside if you need to cover old devices.
Can I get a transparent background?
If the source already has an alpha channel (ProRes 4444, or a WebM with alpha), it is preserved. Converting from an opaque MP4 will not invent transparency.
How fast is it?
Slightly slower than converting to MP4, because VP9 encoding costs more. A five-minute 1080p clip usually finishes in a few minutes.
Does the audio survive?
Yes.