HDMI 1.4 supported 4K resolution at up to 30 frames per second, but HDMI 2.0's 4K60 compatibility set the standard for watching 4K content on a 4K TV. HDMI 2.1 skips the 30fps step for 8K (7,680 by 4,320) and jumps straight to enabling the new, much higher resolution at 60fps.