Netflix announced last week that it is getting offline video downloads support. The company has since shared that it is using VP9 video compression codec to ensure that the file sizes don't weigh a lot. An anonymous reader shares an article on Slashgear (edited): For streaming content, Netflix largely relies on H.264/AVC to reduce the bandwidth, but for downloading content, it uses VP9 encoding. VP9 can allow better quality videos for the same amount of data needed to download. The challenge is that VP9 isn't supported by all streaming providers -- it is supported on Android devices and via the Chrome browser. So to get around that lack of support on iOS, Netflix is offering downloads in H.264/AVC High whereas streams are encoded in H.264/AVC Main on such devices. Netflix chooses the optimal encoding format for each title on its service after finding, for instance, that animated films are easier to encode than live-action. Netflix says that H.264 High encoding saves 19% bandwidth compared to other encoding standards while VP9 saves 36%.