Hair typically grows about half an inch (approximately 1.27 centimeters) per month on average. This translates to roughly six inches (15 centimeters) per year
. However, this is an average figure and individual hair growth rates can vary significantly. Factors influencing hair growth rate include genetics, age, sex, ethnicity, health, nutrition, and hair care practices. For example, hair growth rates can range from about 0.2 inches (5 mm) per month in people of African descent to up to 0.8 inches (20 mm) per month in people of Asian descent
. The Trichological Society notes a broader range of 0.5 to 1.7 centimeters (0.2 to 0.7 inches) per month depending on these factors
. In summary:
- Average hair growth: ~0.5 inch (1.27 cm) per month
- Possible range: 0.2 to 0.7 inches (0.5 to 1.7 cm) per month
- Annual growth: about 6 inches (15 cm) on average, but can vary from about 4 to 8 inches (10 to 20 cm) depending on individual factors
Hair growth is not constant for every strand, as hair follicles cycle through growth phases, and environmental or health factors can affect how much length is retained due to breakage
. Thus, while half an inch per month is a good general estimate, actual growth can be slightly less or more depending on the person.
