How small are pixilels?

Pixels, the smallest units of a digital image, vary in size depending on the display resolution and technology. In modern screens, they can be as small as 0.1 millimeters or less in high-resolution displays like 4K and 8K. Although individual pixel sizes are tiny, they contribute to the overall image quality and clarity when viewed at a normal distance. The concept of pixel density, measured in pixels per inch (PPI), further defines how compactly these pixels are arranged on a screen.