Understanding the Norwood Hair Scale [WITH PICTURES]

Understanding the Norwood Hair Scale [WITH PICTURES]

Scientists studying Mendelian genetics recognized male baldness as an inherited condition as early as 1914.

However, it wasn't until the late 1940s that the term "male pattern baldness" entered the field of dermatology.

Around 1953, an anatomist named James Hamilton developed an interest in premature baldness and created a system to classify the stages of hair loss in men. Initially called the Hamilton Scale for baldness in men, it was later updated in the 1970s by dermatologist O'Tar Norwood.

Today, this hair loss chart and scale is referred to as either the Norwood-Hamilton hair loss scale or the Norwood balding scale.

Understanding the Hamilton-Norwood Hair Loss Scale

Intended to gauge the status of androgenic alopecia (male or female pattern hair loss) in adults, the Norwood scale is sometimes used by physicians who suspect a patient may have a serious condition. For example, lupus, rheumatoid arthritis, and hypothyroidism can cause premature hair loss in men and women.

Applying the Norwood hair scale to hair loss cases may provide insight into the progression of a disease with late-onset of symptoms.

The Hamilton-Norwood scale is comprised of seven specific stages (types) of hair loss:

Stage One

Negligible hair loss without a visibly receding hairline.

Stage Two

Minimal hair loss around temples and/or insignificant areas of hair recession at the hairline stretching over the forehead.

Stage Three

Obvious hair thinning, baldness, and a deeply receding hairline close to the temples. At this stage of androgenic alopecia, the "pattern" aspect of male balding begins to look like a U or V. Some people may notice hair loss around or at the crown of their head.

Stage Four

Little to no hair covers the vertex (top middle of the head). Although there is additional hair loss on the crown and at the temples, a small amount of hair still differentiates the two balding areas from each other. Hair growing on the sides of the head continues to present normal thickness.

Stage Five

Hair growth that normally separates the crown of the head and the temples is significantly smaller or narrower than the hair band seen in stage four. Hair thinning is severe enough to reveal portions of the scalp.

Stage Six

At this stage, the top of the head is completely bald or sparsely covered with hair. There is no division of hair loss areas since hair growth is nonexistent.

Stage Seven

The classic horseshoe pattern indicative of male pattern hair loss is clearly defined, with the remaining band of hair encircling the head thinning rapidly. Stage seven is the final stage of the Norwood balding scale and the most severe.

Although this hair chart is the most detailed method of classifying the different phases of androgenic alopecia, it is not always used for determining what kind of hair implant surgery or hair loss treatment should be applied. Dermatology surgeons say the Norwood Hamilton hair loss scale is too general because it does not include unusual types of baldness.

Norwood Scale

Watch this short video on the Norwood Scale here.

What Is the Norwood Class A Version of the Norwood Scale?

After his initial hair loss chart was approved and accepted by dermatologists, Dr. Norwood later expanded his chart by developing the Norwood Class A scale. Pertaining to less common types of progressive hair loss, this scale involved specific contouring of hairline recession that does not include bald patches at the head's vertex.

Unique characteristics of the Norwood Class A hair chart that differentiate it from the Norwood-Hamilton hair loss scale include:

  • Transitioning of the hairline from front to back without the presence of hair in the mid-frontal region of the head
  • Formation of bald areas on the vertex (highest point of the head) do not occur as a result of the hairline recession. Instead, a man's receding hairline will keep moving further to the back of the head without the loss of hair on top of the head.

Dermatologists may rely on the Norwood Class A version when patients present atypical signs of androgenic alopecia.

The Savin Hair Loss Scale

Developed by Dr. Ronald Savin in the 1990s, the Savin scale focuses on female pattern hair loss instead of male pattern hair loss.

Consisting of nine digital images depicting the various stages of crown hair density, the Savin scale measures the loss of hair in three different areas of a woman's scalp:

Around the temples and hairline: The Savin scale assigns alphanumeric codes (F1 to F6) for the various degrees of hair loss around the temples and hairline. F1 indicates minimal hair recession, while F6 indicates that hair recedes back to the mid-scalp.

Middle of the scalp: The alphanumeric codes range from M1 (normal hair part showing negligible scalp) to M5 (visible, roundish area of hair loss or thinning in the middle of a woman's scalp).

Crown and center back of the head: The alphanumeric does for this description range from V1 (minimal loss of hair) to V7 (large area of hair loss affecting the posterior scalp).

Savin Scale

How Is the Norwood Scale Useful for Dermatologists?

Physicians and dermatologists rely on the Norwood-Hamilton hair loss scale to establish an initial diagnosis, monitor thinning and loss of hair, and as a standard for keeping track of treatment efficacy.

In addition, the Norwood scale is a valuable tool to aid in determining what kind of hair loss treatment would work best on patients with androgenic alopecia.

For example, minoxidil or finasteride are often prescribed to delay the progression of male pattern baldness when in its early stages. Women with female pattern baldness also benefit from minoxidil, though they cannot take finasteride.

Best Ways to Treat Hair Loss

For men and women dealing with hair loss due to androgenic alopecia or any other kind, the good news is that effective, easy-to-use options exist.


Minoxidil is one of the most common and affordable options for hair loss treatment. It’s been clinically proven to improve hair density and growth for a majority of people who use it consistently, and it’s safe for all hair types. The longer you use it, the better the results.

Minoxidil is applied twice daily at 2% or 5% concentrations for women and men respectively.


Finasteride is another great option. Approved as the only oral pill for hair loss over twenty years ago, it can improve density, thickness, and even help regrow lost hair.

Finasteride is only for men, and it’s taken once a day as a pill. Finasteride is not safe for women.

Shapiro MD Kits

Shapiro MD is home to some of the most popular natural hair loss formulas on the market, invented by dermatologists as a simple solution for all of their hair loss patients.

Shapiro MD’s Regrowth Kit contains our patented Shampoo, Conditioner, Leave-in Foam, and minoxidil. It’s a great option for those who want to attack hair loss and growth aggressively. And, it’s easy –– apply minoxidil daily and use the Shampoo, Conditioner, and Foamer as part of your normal showering routine.

Terms Associated With the Norwood Scale and the Treatment of Androgenic Alopecia

Alopecia: hair loss due to genetics, illness, or disease. Basically any non-specific form of hair loss.

Anagen: the growing phase of all body hair. The anagen phase can be as short as one year or as long as seven years.

Catagen: hair growth stage between the telogen (resting) and anagen (growing) stage. The telogen stage comes after the catagen stage.

Dihydrotestosterone (DHT): a hormone that is the primary cause of follicle miniaturization that contributes to hair loss.

Female pattern baldness: attributed to aging, hormonal imbalances, and genes, female pattern baldness progresses slower than male pattern hair loss.

**Finasteride (**brand name Propecia): an anti-androgen that inhibits a certain enzyme from forming DHT. In addition to being prescribed for hair loss, finasteride is FDA-approved to treat benign prostate enlargement.

Ketoconazole: an antifungal agent found in an over-the-counter shampoo called Nizoral, ketoconazole has anti-androgenic properties that may promote hair thickness and/or growth.

Minoxidil (Rogaine): a medication available by prescription only. Minoxidil is used as a topical to slow hair loss and/or stimulate hair growth. It is also prescribed orally to reduce high blood pressure.

Retin-A: primarily prescribed to treat acne, Retin-A may help delay hair loss in some cases, especially when it is used in conjunction with minoxidil.

Spironolactone (brand name Aldactone): a diuretic that also reduces testosterone in women. Spironolactone is sometimes prescribed to treat female pattern baldness.

Tretinoin (all-trans retinoic acid): ATRA is the generic name for Retin-A.

To see all of the great options from Shapiro MD and order today (we can even prescribe finasteride online!) click here to get started.





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