Hair Growth Calculator
Wondering how long it will take to grow your hair out? Enter your current and desired hair lengths and select your hair type to get a realistic timeline. The calculator accounts for hair shrinkage in curly and coily textures and includes extra time for recommended trims.
On average, human hair grows approximately 0.5 inches (1.25 cm) per month, or about 6 inches per year. However, the apparent growth rate varies by hair type:
- Straight hair (Type 1): ~0.50 in/month, hangs at full length, so actual and apparent growth are the same
- Wavy hair (Type 2): ~0.48 in/month, slight shortening from wave pattern
- Curly hair (Type 3): ~0.44 in/month, coils cause 10-20% shrinkage
- Coily hair (Type 4): ~0.38 in/month, tight coils cause 25-75% shrinkage, so hair appears much shorter than its actual length
The estimate includes a 10% time buffer for regular trims, which are essential for maintaining healthy hair during the growing process. Trimming 1/4 to 1/2 inch every 8-12 weeks prevents split ends from traveling up the hair shaft and causing breakage, which would actually slow your progress.
Factors that can affect your growth rate include genetics, age, diet, stress, hormonal changes, and hair care practices. Maintaining a healthy diet rich in protein, biotin, and iron supports optimal hair growth.