Skin Depth Calculator

At RF frequencies, current crowds near the conductor surface — the skin effect. The skin depth δ is the depth at which current density falls to 1/e of its surface value. Conductor thickness should be ≥ 3–5 skin depths to carry current efficiently.

Equations & Parameters ▸

\(\delta = \sqrt{\dfrac{2}{\omega\mu\sigma}}\)

f	Frequency. Skin depth decreases with √f.
σ	Electrical conductivity (S/m). Copper ≈ 5.8×10⁷, aluminium ≈ 3.8×10⁷, silver ≈ 6.3×10⁷.
δ	Skin depth = √(2/ωμσ). Below this depth, current is negligible.

Physical constants used

c	Speed of light = 2.998×10⁸ m/s
µ₀	Permeability of free space = 4π×10⁻⁷ H/m
σ_Cu	Copper conductivity = 5.8×10⁷ S/m
σ_Al	Aluminium conductivity = 3.8×10⁷ S/m
σ_Ag	Silver conductivity = 6.3×10⁷ S/m

Inputs

Frequency, f

Conductor material

Custom conductivity σ

S/m

Enabled when Custom selected above

Results

Skin Depth

δ (skin depth)—

δ (metres)—

Diagram

📖 Learn about the skin effect →