Hair Classification

The Norwood Classification

A system of hair loss classification is a useful way to help doctors compare patients. The Norwood Classification is the most commonly used for male pattern baldness.

There are two basic patterns, the most common of which is where hair loss starts in two different areas – the temples and the crown of the head.

Less common patterns feature the hair loss progressing from the front to back.

Non-genetic hair loss from other causes usually follows a completely different pattern again.

Explanation of Classifications

Type I

• No recession
• “Adolescent” hairline

Type II

• Temporal recession less than 2.5cm
• Mild recession along frontal hairline
• “Mature” hairline

Type III

• Further frontal hairline recession
• Deeper recession at corners, “zipper” opening
• Primary stage of balding

Type III Vertex

• Hairloss predominantly in vertex (crown)
• Frontal hairline recession may be present

Type IV

• Further frontal hair loss and temporal recession
• Enlargement of crown (bald spot)
• Solid band of hair across top separating the frontal area from the crown

Type V

• Frontal and temporal balding areas enlarge even further
• Band separating the two areas becomes narrower and less dense

Type VI

• Frontal and crown balding areas merge into one and increase in size

Type VII

• Only a narrow horseshoe band of hair remaining
• Low hairline in the back
• Hair in permanent zone may be sparse

Type A Variant

• Frontal hairline recession keeps advancing backwards
• Single area of balding
• Eventual extent of balding tends to be more limited than in regular Norwood classes

Type IIa

• Entire frontal hairline recedes

Type IIIa

• Frontal hair loss extends to the mid scalp

Type IVa

• Hair loss moves past mid scalp area

Type Va

• Hair loss extends towards the crown
• Back part of the bald area is narrower than in the regular Norwood VI