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YouTube: YouTube is the biggest and most famous video website in the world. It provides videos of variousresolutions from 480P to 4K (3840*2160). You can easily get access to any kinds of videos of 4K including some TV episodes, video demos, documentaries and some movies without registration unless you want to see some 18+ ones which request your registration of ID confirmation.
Vimeo: Vimeo is the second best video website next to YouTube. It began to provide 4K video streaming and uploading at the end of 2015. It contains thousands of 4K clips including those VR videos, advertisements, documentaries, some TV series, movies and trailers. You can choose ultra-definition or standard definition when watching
Metacafe: Metacafe is another good free 4K video site whose site is in San Francisco, California. It supports 4K, the codec of H265 which enables users to stream 4K videos at a much lower bit rate.Metacafespecializes in short-form video entertainment in the categories of movies, video games, sports, music and TV. Moreover, you can share your videos by uploading to let everybody sees.
Daily Motion: Daily Motion is a video-sharing website based in France on which users can upload, watch and share videos. It is one of the most renowned video platforms in the world, offering a mix of content from users, independent creators and premium partners. As for 4k movies, you can watch old movies and there are more other 4K contents available, for example, 4K documentary and 4K concerts of some famous stars. Like those websites above, you can directly watch whatever you want without registration.
Netfilix: This is a real movie (including 4K) downloading paid websites. It specializes in providing streaming media and video-on-demand online and DVD by mail.You can get all kinds movies including those latest ones and download them once getting registered and pay with your credit card.