Wire DC resistance calculator

This calculator calculates the DC resistance of a wire.

The multiplier field can be used to factor in return path (multiplier=2), or R_rf/R_dc resistance factor from Skin depth calculator.

Resistivity and permeability

Resistivity of a material is the resistance from face to opposite face of a 1m cube of a material. Resistivity varies with different metals, a few common conductors are listed below.

Permeability is the ratio of flux density to magnetising force, self inductance is proportional to permeability.

Conductor	Resistivity (µΩ-m)	Conductivity (MS/m)	Relative Permeability (µ_r)
Copper	0.0168	59.52	1
Silver	0.0159	62.89	1
Aluminium	0.0282	35.46	1
Aluminium 7xxx annealed	0.045	22.22	1
ZA ZAL	0.059	17	1
Zinc	0.059	16.95	1
Brass	0.064	15.63	1
Nickel	0.064	15.63	1240
Iron	0.100	10.00	200
Tin	0.109	9.17	1
Solder (63/37 Eutectic)	0.145	6.90	1
Mild steel	0.20	5.00	800
Lead	0.22	4.55	1
Stainless steel 316	0.75	1.33	1
Stainless steel 17-7 PH	0.82	1.22	120

A note about stainless steels. Pure austenitic steels do not exhibit ferro magnetism, relative permeability is unity. Many stainless steels are austenitic, but the process of hardening them, or the hardening as a result of working them (eg drawing wire) can create martensite, and they may exhbit µ_r significant greater than unity. Be suspicious of hardened stainless steel, check it with a magnet. If it is attracted to the magnet, it may have high µ_r and as a result may have quite high RF resistance. Stainless 316 tends to not develop ferromagnetism with work, 304 a little, and in the table above, 17-7PH has quite high µ_r in the hardened state (you wouldn't use it in the annealed state).

Examples

Example 1

References / links

Other VK1OD tools.

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Length (m)
Multiplier

Diameter (mm)
Radius (mm)
CSA (mm^2)
Resistance (Ω)