Two different measurements
Thickness (strand diameter): How thick each individual hair is.
- Fine: Thinner than sewing thread
- Medium: About sewing thread width
- Coarse/thick: Thicker than sewing thread, may feel wiry
Density (hairs per square centimeter): How many hairs you have on your head.
- Low: You can see scalp easily even when parted normally
- Medium: Scalp visible only when parting directly
- High: Scalp very hard to see even when parting
You can have any combination:
- Fine + low density (looks "thin")
- Fine + high density (lots of fine hairs, feels full)
- Coarse + low density (few but thick strands)
- Coarse + high density (the heaviest, thickest-looking hair)
Why it matters for products
Fine strands
Weigh down fast. Need:
- Lightweight products
- Avoid heavy butters, oils, silicones
- Volume-building ingredients
Coarse strands
Can handle rich products. Need:
- Heavier creams and butters
- Penetrating oils
- More slip for detangling
Low density
Scalp shows through. Styling matters more than products for visual volume:
- Layered cuts
- Root-lift spray
- Dry shampoo for lift
High density
Lots of hair to manage. Products sit differently:
- Need enough product (under-applying is common)
- Section hair for application
- Drying takes longer
How to test thickness
Take a single hair between your fingers:
- Can't feel it → fine
- Feel it faintly → medium
- Feel it clearly like thread → coarse
Or compare to sewing thread — finer, similar, or thicker.
How to test density
Gather all hair into a ponytail. Measure circumference with a tape measure:
- Under 5 cm → low
- 5–10 cm → medium
- Over 10 cm → high
Or part your hair normally and look at how visible your scalp is.
Why people confuse them
"I have thick hair" usually means a lot of hair (density), not that each strand is thick. Conversely, "my hair is thin" often means few strands, not that strands are fine.
Stylists and most products don't distinguish — they lump both into "thick" or "thin." But they need different care.
The Mutaly quiz distinguishes
The Mutaly quiz asks about thickness and density separately to make sure product weight and routine match both.