A micron is a unit of measure in the metric system equal to 1 millionth of a meter in length (about 39 millionths of an inch). The average cross-section of a human hair is 50 microns. The human eye cannot see anything smaller than 40 microns in size.
How thick is a strand of human hair?
As a person grows up, their hair becomes thicker and stronger. Another factor is that, the closer to the root of the hair, the thicker a strand of hair would be. In my research, I have found the diameter of human hair to range from 17 to 181 µm (millionths of a meter).
How thick is a human hair in nanometers?
A sheet of paper is about 100,000 nanometers thick. A strand of human DNA is 2.5 nanometers in diameter. There are 25,400,000 nanometers in one inch. A human hair is approximately 80,000- 100,000 nanometers wide.