How Fast Does Hair Actually Grow?

Table of Contents (click to expand)

The average rate of human hair growth is 0.4 inch (1 cm) per month. However, this rate varies depending on body region, gender, age, hair color and ethnicity.

Scalp hair grows at an average rate of 0.4 inch (1 cm) per month.

  1. Scalp hair growth – 0.014 inches/day (0.36 mm/day)
  2. Eyelash/brow growth – 0.006 inches/day (0.16 mm/day)
  3. Beard hair growth – 0.015 inches/day (0.38 mm/day)

A hair length of 12 cm represents a hair growth of about 3½ to 20 months. Also, hair growth varies depending on body region. In addition to that, growth rate of hair is affected by gender, age, hair color and ethnicity too.

Do you remember that time when you went to a new salon and asked for a simple haircut, but ended up looking like you’d stuck a finger in an electrical socket?


Getting a bad haircut can be traumatic, to say the least, particularly when you need to wait for your hair to grow back. You wake up every morning, hoping against hope that your hair has miraculously fixed itself, but it seems like months before you can properly fix it.

This universal and embarrassing problem begs an important question: How fast does it normally grow? And is there any way to speed up the process?

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Watching Water Boil Vs. Watching Hair Grow

As they say, “a watched pot never boils”, and the same thing is true of human hair. On average, human hair grows at a rate of about half a millimeter per day. Don’t get too excited, as that only equals about half an inch per month. Therefore, people waiting for their hair to grow back after a particularly terrible trim need to have some patience. It will take at least a season to bring back those beautiful locks that got chopped off.


Perception is a big factor in the appearance of hair, because if you have a very short haircut, the change in appearance will be much more dramatic. A crewcut will seem to grow very rapidly, doubling in length in a week or less, whereas a women with hair to the middle of her back will not notice the change in length, despite the relatively even growth rates.

This slow growth of hair is particularly annoying for people who are already beginning to lose their hair and want to have a bit more hair to “work with”. This has led many people to seek ways to boost or speed up hair growth, but is it really possible?

Also Read: Why Do We Lose Hair From Our Head, But Not The Rest Of Our Body?

The Secret To Fast-Growing Hair

That title may actually be a bit inappropriate, because the methods of speeding up hair growth are far from secrets! People have been managing their lifestyle, diet, and behaviors for thousands of years to alter the growth patterns and rates of their hair.

First of all, you need to understand that hair is a very simple material, primarily made up of water, sulfur, and protein. The sulfur content in your hair is why it smells so bad when you singe one of your locks with a match by accident! By adding more of these three substances to your diet, such as by adding fish, eggs, garlic, and green vegetables to your daily meals, and washing it down with 6-8 pints of water per day, you can definitely speed up hair growth. Also, avoiding sugar and high-starch foods, which slow down hair growth, is another viable option.


Blood flow to the scalp is another surefire way to stimulate growth and increase the overall health of your hair. Some of the best ways to boost blood through the blood vessels of the scalp, besides a luscious head massage, is regular exercise. When your heart rate increases, the blood is boosted to all parts of the body, so a short job or cardiovascular exercise every day can keep the hair packed with nutrients and oxygenated blood. This can strengthen the hair root, clear toxins from the sebaceous glands, and keep the tissue healthy and strong.

Also Read: Why Don’t Eyebrows And Eyelashes Grow As Long As Head Hair?

Turn Things On Their Head

Inversion therapy, as the name somewhat suggests, involves spending large periods of time upside down. For over two millennia, the act of inverting your body to the Earth has been used to significantly increase blood flow to the head, in addition to stretching the spine and relieving tension. This heavy blood flow to the head is also an effective way to clear out toxins, ensure nutrient delivery to the follicle beds, prevent further hair loss, and speed up hair growth.


In fact, for people losing their hair or suffering from male pattern baldness, inversion therapy has been shown to be an effective treatment for regrowing lost hair! There are a number of contraptions and methods of practicing inversion therapy, including standing on your head!

What Should I Avoid For Speedy Hair Growth?

Aside from things you can do to improve hair growth, there are also certain things to avoid. Namely, putting tons of harsh chemicals in your hair, whether for styling or changing its color. These harsh chemicals can permanently damage your follicles or “fry” your hair, which definitely slows down growth.

You should also be aware of how often you blow-dry of straighten your hair, as this type of intense heat can increase hair breakage and loss. Using old brushes or combs, or those that are rough on the scalp, can also increase hair loss and damage follicle beds, resulting in slower hair growth. Every head of hair is different, and you should make sure that you understand the right tools, brushes, products, and styling techniques for your individual head! In other words, never be like this guy…


While these techniques won’t result in a full head of hair overnight, by boosting a few millimeters of growth every day, over the course of months and years, your hair can grow to its full potential!

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References (click to expand)
  1. ATSDR Hair Analysis Panel Discussion: Section 2.4. The Agency for Toxic Substances and Disease Registry
  2. How fast does hair grow? | Live Science. Live Science
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About the Author

John Staughton is a traveling writer, editor, publisher and photographer who earned his English and Integrative Biology degrees from the University of Illinois. He is the co-founder of a literary journal, Sheriff Nottingham, and the Content Director for Stain’d Arts, an arts nonprofit based in Denver. On a perpetual journey towards the idea of home, he uses words to educate, inspire, uplift and evolve.