What is the resolution of 4K? 4K resolution, at least the way most TVs define it, is 3840 x 2160 or 2160p. To put that in perspective, a full HD 1080p image is only a 1920x1080 resolution. 4K screens have about 8 million pixels, which is around four times what your current 1080p set can display.
Think of your TV like a grid, with rows and columns. A full HD 1080p image is 1080 rows high and 1920 columns wide. A 4K image approximately doubles the numbers in both directions, yielding approximately four times as many pixels total. To put it another way, you could fit every pixel from your 1080p set onto one-quarter of a 4K screen.
Why is it called 4K? Because the images are around 4,000 pixels wide. And before you ask, yes, the industry named 1080 resolution after image height, but named 4K after image width.
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