Top best answers to the question «Does hd look bad on 4k tv»
Most 4k TVs will upscale 1080p content to 4k. While this is not going to actually equal the quality of true 4k content, it should come close, and good quality 1080p content should look better when upscaled onto a 4k screen than it did on a 1080p screen.
Standard-definition TV, DVD and even 720p HDTV programs aren't going to look any better on a 4K TV. You can't get water from a stone. And it's worth remembering that the more you sharpen an image, the more you accentuate the flaws present in lower-grade content, such as noise or macroblocking.
Originally Answered: Do 1080p videos look bad on 4k TVs? No, they look OK. There's good reason for that: 4K aka 2160p has exactly 4 times bigger pixel count than 1080p, so when upscaling, every pixel from the 1080p source is rendered by exactly 4 pixels on 4K screen.
It depends on a number of factors, including the quality of the video, the quality of the upscaling, and the perception of the individual, but in general no, 1080p videos do not look bad on 4K TVs and can actually look quite good.