How small are human cells compared with a pinhead?

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biology; microscope — Biology A researcher using a microscope to examine a specimen in the laboratory.

Human cells are microscopic, typically measuring about 20 μm across. Because of their tiny size, it would require a sheet of approximately 10,000 human cells to cover the head of a pin.1

While individual cells are small, they are the fundamental building blocks of the human body, which is composed of more than 30 trillion cells in total.1