Hair density, shaft diameter, and curl pattern vary significantly across ethnic groups, and any AI-based hair loss assessment must account for these differences to produce accurate Norwood staging. The myhairline.ai tool uses 468 MediaPipe facial landmarks combined with ethnicity-aware density calibration to deliver precise results regardless of hair type.
This article is for informational purposes only and does not constitute medical advice. Consult a physician for clinical diagnosis.
Why Ethnicity Matters in Hair Loss Assessment
Not all hair is the same. A hair density reading that suggests Norwood 3 in a Caucasian male may be perfectly normal for an Asian or African male whose baseline density is naturally different. Without calibration, AI tools produce inaccurate results for non-Caucasian users.
Follicular Density by Ethnicity
| Ethnic Group | Follicular Units per cm2 (Range) | Average FU/cm2 |
|---|---|---|
| Caucasian | 170 to 230 | 200 |
| African | 120 to 180 | 150 |
| Asian | 140 to 200 | 170 |
| Hispanic | 145 to 195 | 170 |
| Middle Eastern | 150 to 210 | 180 |
These ranges come from published trichoscopy studies and are built into the myhairline.ai assessment algorithm.
Hair Shaft Diameter Differences
| Ethnic Group | Typical Shaft Diameter | Visual Coverage Impact |
|---|---|---|
| Caucasian | 60 to 80 micrometers | Moderate per-strand coverage |
| African | 55 to 75 micrometers (elliptical cross-section) | High visual coverage due to curl |
| Asian | 80 to 100 micrometers | High coverage due to thickness |
Asian hair shafts are typically the thickest (80 to 100 micrometers), providing more visual coverage per follicle. African hair has an elliptical cross-section and tighter curl pattern, which creates volume and coverage despite lower follicular density. Caucasian hair falls in the middle on both measures.
How myhairline.ai Adjusts for Hair Type
The free AI tool at myhairline.ai/analyze performs adjustments in three stages:
Stage 1: Facial Landmark Mapping
The system plots 468 MediaPipe facial landmarks to identify:
- Forehead boundary and hairline position
- Temple recession depth
- Vertex area dimensions
- Facial proportions relative to the golden ratio (1.618)
This landmark mapping works identically across all ethnicities because it measures geometric relationships, not hair characteristics directly.
Stage 2: Hair Type Calibration
Based on user input and image analysis, the system adjusts its density thresholds:
| Calibration Factor | What It Adjusts |
|---|---|
| Baseline density expectation | Sets the "normal" reference point for your ethnic group |
| Coverage per follicle | Accounts for shaft diameter and curl pattern |
| Miniaturization threshold | Adjusts what counts as thinning vs. natural density |
| Scalp visibility weighting | Lighter scalps show through more easily; darker scalps less so |
Stage 3: Norwood Classification
With calibrated thresholds, the AI assigns a Norwood stage that accurately reflects your degree of hair loss relative to your ethnic baseline, not a universal average.
What This Means for Treatment Planning
Accurate staging directly impacts treatment recommendations.
Graft Count Adjustments
Because baseline density varies, transplant graft counts may need adjustment by ethnicity:
| Ethnic Group | Average FU/cm2 | Safe Extraction Limit (45%) | Relative Donor Capacity |
|---|---|---|---|
| Caucasian | 200 | 90 FU/cm2 extractable | Highest |
| Middle Eastern | 180 | 81 FU/cm2 extractable | High |
| Asian | 170 | 76.5 FU/cm2 extractable | Moderate |
| Hispanic | 170 | 76.5 FU/cm2 extractable | Moderate |
| African | 150 | 67.5 FU/cm2 extractable | Lower (but each graft covers more) |
The safe extraction limit is 45% of total donor density. Exceeding this creates visible donor thinning.
African hair types often require fewer grafts than the standard Norwood chart suggests because each strand's curl pattern provides greater visual coverage. An average of 2.2 hairs per graft combined with the elliptical shaft creates volume that straight-haired patients need more grafts to achieve.
Medication Efficacy Across Ethnicities
Current data on finasteride and dutasteride comes primarily from Caucasian and East Asian study populations:
| Treatment | Caucasian Data | Asian Data | African Data |
|---|---|---|---|
| Finasteride 1mg | 80 to 90% halt, 65% regrowth | Similar efficacy confirmed | Limited study data |
| Dutasteride 0.5mg | >90% DHT reduction | Approved in South Korea/Japan; strong data | Very limited data |
| Minoxidil 5% | 40 to 60% regrowth | Similar efficacy | Similar efficacy reported |
The relative lack of clinical trial data for African hair types is a recognized gap in the research. Treatment efficacy is believed to be similar, but more studies are needed.
How to Use the Tool
- Visit myhairline.ai/analyze on any device with a camera
- No account needed. No photos stored or uploaded to servers.
- Position your face in the frame following the on-screen guide
- The AI maps 468 facial landmarks and analyzes your hairline
- Receive your calibrated Norwood stage assessment in under 60 seconds
The tool works in any modern browser on phone, tablet, or desktop. All processing happens locally on your device.
Limitations
- The AI provides a screening assessment, not a clinical diagnosis
- Tightly coiled or very short hairstyles may reduce landmark detection accuracy
- Head coverings, hats, or styling products can interfere with the analysis
- A dermatologist visit with trichoscopy remains the gold standard for definitive staging
For more on how AI hair analysis works, read the AI hair loss analysis guide. To understand the Norwood scale in detail, see the Norwood scale complete guide.
This article is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider for clinical diagnosis and treatment planning.