Health & Beauty

Hair Growth Calculator

Predict growth timelines, analyze health factors, and optimize your hair care routine.

1. Your Hair Measurements

in
Measure from root to tip when straight.
in

2. Your Profile

All types grow ~0.5"/mo from the follicle. Coily hair appears shorter due to shrinkage.
Growth rates vary by ethnic background due to follicle shape.
Females average slightly faster hair growth due to estrogen.
Hair grows 10–15% faster in warm months.

Lifestyle & Nutrition Factors

These factors influence how fast your hair grows and how much length you retain.

Protein, iron, zinc, omega-3s all drive keratin production.
Growth hormone is released during deep sleep cycles.
Chronic stress can trigger telogen effluvium (shedding). 1 = calm, 10 = extreme.
Exercise improves scalp circulation and nutrient delivery.
Biotin (5000mcg) + vitamin D + iron is the most evidence-backed combo.
Studies show daily 4-min scalp massage increases hair thickness.

Hair Health Assessment

Evaluate your current hair and scalp condition for a health score and targeted advice.

Growth Timeline Generator

See your month-by-month hair growth journey. Uses your profile from the Growth Calc tab.

How Hair Growth Works

Hair grows from follicles in a 3-phase cycle: Anagen (active growth, 2–7 years), Catagen (transition, 2–3 weeks), and Telogen (resting/shedding, 3 months). At any time, ~85–90% of your hair is in anagen phase.


Key growth facts:
• Average rate: ~0.5 inches/month (~6 inches/year) from the follicle.
• Genetics: Your anagen phase length is genetically determined — this is why some people can grow hair to their waist and others can't get past shoulder length.
• Ethnicity matters: Asian hair grows fastest (~0.55"/mo), Caucasian ~0.50", African ~0.45" — due to follicle shape differences.
• Season: Hair grows 10–15% faster in summer due to increased blood flow and vitamin D.
• Length retention ≠ growth: Your hair may grow 6"/year but if 4" breaks off, you only retain 2". Retention is everything.
Tips to Maximize Growth & Retention
1. Protective styling: Braids, buns, and silk scarves reduce mechanical damage and breakage at the ends.

2. Satin/silk pillowcase: Cotton pillowcases create friction that causes breakage and frizz. Switch to satin.

3. Scalp massage: 4 minutes daily increases blood flow to follicles. A 2016 study showed increased hair thickness after 24 weeks.

4. Trim strategically: Trim 0.25–0.5" every 10–12 weeks to prevent split ends from traveling up the shaft. Don't skip trims trying to "save length."

5. Deep condition weekly: Moisture is the #1 factor in length retention. Use a protein-moisture balanced routine.

6. Minimize heat: Every heat pass damages the cuticle. Air dry when possible, always use a heat protectant, and keep tools under 350°F.