To that end, all new videos uploaded to YouTube are now transcoded into WebM. WebM is an open media file format for video and audio on the web. Its openness allows anyone to improve the format and its integrations, resulting in a better experience for you in the long-term. As we work to transcode more videos into WebM, we hope to reduce the technical incompatibilities that prevent you from accessing video while improving the overall online video landscape.

Transcoding all new video uploads into WebM is an important first step, and we’re also working to transcode our entire video catalog to WebM. Given the massive size of our catalog - nearly 6 years of video is uploaded to YouTube every day - this is quite the undertaking. So far we’ve already transcoded videos that make up 99% of views on the site or nearly 30% of all videos into WebM. We’re focusing first on the most viewed videos on the site, and we’ve made great progress here through our cloud-based video processing infrastructure that maximizes the efficiency of processing and transcoding without stopping. It works like this: at busy upload times, our processing power is dedicated to new uploads, and at less busy times, our cloud will automatically switch some of our processing to encode older videos into WebM. As we continue to transcode the remaining inventory, we’ll keep you posted on our progress.

In keeping with our goal of making videos universally accessible, we will continue to support H.264 as an important codec for video on YouTube. We are also committed to continuing to develop our HTML5 video player that we announced last year, and if you’d like to join the opt-in trial, you can do so here.