Hair Density Guide: What It Is & Why It Matters
Hair density is one of the most important metrics for understanding your hair health. Learn how to interpret it and track changes that matter.
Understanding Density Levels
Hair density is measured in hairs per square centimeter. The average person has about 100,000–150,000 hairs total, distributed across approximately 600 cm² of scalp.
Low Density
< 100 hairs/cm²
Scalp is visible through the hair, especially when wet or in bright light. Hair may appear thin and wispy. Common in later stages of hair loss.
Medium Density
100–150 hairs/cm²
Average hair density. Scalp may be partially visible in certain lighting. Most people fall into this category naturally.
High Density
> 150 hairs/cm²
Thick, full hair with minimal scalp visibility. Hair appears voluminous and can hold styles well. Typical of younger individuals without hair loss.
Hair Density vs. Hair Thickness
Density
How many hair strands grow per unit area of scalp. Density determines how "full" your hair looks from a distance. Lower density means more scalp visibility.
- • Measured in hairs per cm²
- • Affects overall coverage
- • Decreases with pattern hair loss
Thickness
The diameter of individual hair strands. Thicker strands provide more coverage even with fewer hairs. Hair miniaturization (thinning strands) is a key sign of androgenetic alopecia.
- • Measured in micrometers (μm)
- • Affects volume and texture
- • Miniaturization is an early DHT-related sign
Track Your Hair Density Over Time
Trichometrics uses AI to analyze your photos and estimate density across different scalp regions. Track changes over weeks and months to see the real impact of your treatments.
Region-by-Region Analysis
See density scores for hairline, crown, temples, and sides.
AI-Powered Precision
No manual counting. AI evaluates density from your photos.
Historical Comparison
Compare density changes side-by-side across months.
Start Tracking Your Hair Density
Upload a photo and get your AI-assessed density score for each scalp region. It's free.
Analyze My Hair DensityFrequently Asked Questions
What is hair density?▾
Hair density refers to the number of hair strands per square centimeter of scalp. It is different from hair thickness (the diameter of individual strands). Someone can have fine hair but high density, or thick individual strands but low density.
How is hair density measured?▾
Clinically, hair density is measured using trichoscopy, a magnified examination of the scalp. Trichometrics uses AI-powered photo analysis to estimate relative density by analyzing scalp visibility, hair coverage patterns, and strand distribution in your photos.
What causes hair density to decrease?▾
Hair density naturally decreases with age. Other causes include androgenetic alopecia (pattern baldness), stress (telogen effluvium), nutritional deficiencies, hormonal changes, medications, and certain medical conditions. Tracking density changes helps identify early hair loss.
Can hair density be restored?▾
Depending on the cause, hair density can often be improved. Treatments like minoxidil can stimulate follicles, finasteride can prevent further loss, and PRP therapy can promote regrowth. Hair transplants can redistribute density. Tracking with Trichometrics helps you measure improvement objectively.