It is said that humans first notice their scalp hair loss only after one-half of existing head hair has disappeared. I am not sure if this is a proven fact. I would have guessed that one would notice significant thinning even after one-quarter of ones locks have disappeared. The normal rate of daily hair loss varies significantly from person to person.
In any event, that got me thinking as to how many hairs there are on an average human head? It seems like the answer is surprisingly easy to find, and researchers are in general agreement about the statistics.
How Many Hairs on the Human Head?
Answer: The range is from 90,000 to 150,000 hairs on the average human head.
A typical human scalp measures 120 square inches (774 square cm). According to Harvard Biological Numbers database, The color of your hair makes a difference as to how many strands are on your head:
- If you are a blonde, you likely have the most hair at birth at around 150,000 follicles.
- Brown haired people have an average of 110,000 hair follicles.
- Black haired people, who represent a majority of the world, are born with 100,000 hairs.
- And last but not least, possibly soon to be extinct redheads have only 90,000 hair follicles. Only 2% of humans are redheads.
Note that the entire human body has around 5 million hair follicles. The only areas of your body that have no hair (vellus or terminal) are the palms of your hands, soles of your feet, nipples, lips and parts of the genital regions.
Density per Square Inch
On a related note, head hair density varies significantly depending on area of scalp, sex, age and ethnicity. On average, men have a scalp hair density of 800 to 1300 hair follicles per square inch. This is equivalent to 125 to 200 hairs per square centimeter.
Women have slightly more hair per square centimeter then men, though females have smaller scalp sizes then males. The areas of the human head can be divided into frontal, parietal, vertex, occipital and temporal.
For those with androgenetic alopecia, hair transplant surgery needs to take account of the varying density depending on the region of the scalp. Moreover, hair follicular unit (grafts) can come in groups of 1-, 2-, and 3-hair units.
This article was originally written on August 27, 2017. Updated on December 9, 2023.