Skin Thickness by Body Region: From Eyelids to Soles

Skin Thickness Variation Across Body Sites

Human skin thickness ranges 0.5–4 mm, varying by location, age, sex, and genetics.

Body Site	Thickness	Characteristics
Eyelids	0.5 mm (thinnest)	Minimal subcutaneous tissue, high vascularity
Genital/axillary	0.5–1 mm	Thin, sensitive
Face/neck	1–1.5 mm	Moderate, high sebaceous activity
Trunk/limbs	1.5–2 mm	Variable subcutaneous fat
Scalp	3–5 mm (with subcutis)	Dense connective tissue, hair follicles
Palms/soles	1.5–4 mm (epidermis only: 0.8–1.5 mm)	Thick stratum corneum, no hair, high sweat glands

Histologic Layers

• Epidermis: 0.05–1.5 mm (stratum corneum major variable).
• Dermis: 1–3 mm (collagen/elastin, vascular, neural).
• Hypodermis (subcutaneous): Highly variable (2 mm–several cm).

Clinical Relevance

• Topical drug absorption: thinner skin = faster penetration.
• Needle/injection depth selection.
• Burn assessment (TBSA, depth).
• Surgical planning (flaps, grafts).
• Aging: dermal atrophy → thinning, fragility.