YouTube Fiddles With 4KYouTube on Friday announced that it would begin supporting Ultra High Definition 4K video content. YouTube officially unveiled the news via TestTube, an incubator for new features concocted by its so-called mad scientists. YouTube developers have posted six experimental videos that can be streamed at up to 2160p -- essentially a resolution of 3,840 x 2,160.
Source:
YouTube Fiddles With 4K