Norwood Hamilton Scale

The Norwood Scale (or Hamilton-Norwood Scale or HN-scale) is the accepted scale used to measure the degree of male hair loss (women are measured using the Ludwig/Savin scale). By comparing actual hair loss against this scale, health practitioners can determine an appropriate course of action to combat the patient’s hair loss. The Norwood scale is useful for people considering hair transplant surgery, as well as a way for other medical researchers to conduct studies into the relationship between male pattern baldness and other medical conditions.

Named after hair loss researchers Dr. James Hamilton and O’Tar Norwood, the Norwood scale was first developed in the 1950’s by Dr. Hamilton, and then later revised some 2 decades later by Norwood.

 The Norwood scale breaks down male pattern baldness into seven distinct categories ranging from type I, meaning no hair loss (or a ‘normal’ head of hair), right through to type VII, depicting near total hair loss with hair remaining only around the base of the skull (at the back and on the sides). Further classifications, using the letters ‘A’ or ‘V’, describe the direction of the hair loss. ‘A’ stands for ‘anterior’, meaning a general ‘front to back’ progression of hair loss while ‘V’, or ‘vertex’ describes a back to front hair loss progression. The Norwood scale only lists the most typical patterns in male baldness, and there are many variations of each pattern, so the scale itself should be used as a general guide only.

One thing to keep in mind if you use the Norwood scale to classify your own hair loss is that the scale only classifies your current condition of hair loss, and should in no way be considered a predictor of hair loss to come or an indicator of the rate at which hair loss might occur.