How Fast Does Hair Grow?

Measuring how fast hair grows
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Q: How fast does hair grow?
A: The speed of hair growth is roughly 1.25 centimeters or 0.5 inches per month, which is about 15 centimeters or 6 inches per year. With age, the speed of hair growth might slow down to as little as 0.25 centimeters or 0.1 inch per month.
Cell division is responsible for the hair growth cycle. The new cells push the hair forward, making it longer, so new hair is added at the root.
There are approximately 100,000 hairs on a healthy scalp. Each of these hairs, under normal, healthy conditions, can last from one to six years. People lose about 100 hairs per day, under normal conditions. The fallen hairs are replaced by new hair. Baldness occurs when new hairs are no longer being produced.
During its life, a hair goes through three phases of growth: the anagen, the telogen and the catagen. The anagen is the first phase, with new hair growing in the hair bulb. The catagen is the following phase when hair stops growing because cell division has stopped. The telogen is the final phase. New hair starts growing in the papilla and the old hair eventually falls out.
The anagen, catagen and telogen phases of hair growth
Hair growth per month - How fast hair grows
Hair grows at about the same speed all over your head, with no perceptible difference between the bangs, nape, crown, etc.
You might think that bangs grow faster than hair on other parts of your head, but that's simply an illusion. Many cut their bangs just above the eyebrows, and because of this, the slightest hair growth is visible.
Wearing a turtleneck can make your hair appear longer and may give the illusion that your hair is growing faster. This is due to the straight line of the turtleneck.
See also:
Hair growth calculation
What exactly is hair made of and how does it grow?