Skin Depth Calculator

Calculate the electromagnetic skin depth δ and surface resistance for common conductor materials.

What is Skin Depth?

At high frequencies, electricity doesn't flow through the entire cross-section of a wire — it flows only through a thin outer "skin," like a river flowing fastest at the surface. The higher the frequency, the thinner this skin gets, so only the surface of the conductor carries the current.

Why it matters: Microwave cables are often silver-plated because at high frequencies only the surface matters — silver has better conductivity than copper, reducing signal loss. At 10 GHz, the skin depth in copper is less than 1 micron.

Parameters
Select material and set frequency.

Copper

ρ = 1.72e-8 Ω·mσ = 5.814e+7 S/mµᵣ = 1
1 Hz1 kHz1 MHz1 GHz100 GHz

Skin Depth
66.006 µm
Surface Resistance
260.582 µΩ/□
Results
Copper at 1 MHz
Skin Depth (µm)
66.0061µm
Skin Depth (mils)
2.5987mil
Skin Depth (meters)
6.6006e-5m
Resistance per Square
260.582 µΩ/□
Conductivity (σ)
5.814e+7S/m
PCB Copper Comparison
0.5 oz (17.5 µm)
0.3× δ
1 oz (35 µm)
0.5× δ
2 oz (70 µm)
1.1× δ