Google's royalty-free video container, built for the web and carrying VP8, VP9 or AV1 video with Opus audio. Every modern browser plays it without a plugin or a licence, which is why it's the sensible choice for video you host yourself and a poor one for video you send to someone's phone.

Every conversion below runs in this page, on your own machine. Nothing is uploaded, there is no queue, and there is no account to make. Pick a target format, or just drop a WebM file above and choose afterwards.