Wire Gauge Resistance Calculator
Estimate wire resistance based on AWG gauge, length, and copper resistivity.
ft
ohm-cmil/ft
One-Way Resistance
0.1588 Ω
Wire Diameter80.81 mils
Round-Trip Resistance0.3176 Ω
One-Way Resistance vs AWG Gauge Number
Wire Gauge Resistance
AWG Diameter
d(mils) = 1000 x 92^((36-AWG)/39) / 200
Resistance
R = rho x L / A
Copper: rho = 10.37 ohm-cmil/ft at 20 C.
Example Calculation
100 ft of 12 AWG copper.
- 01Diameter = 80.81 mils
- 02Area = 6530 cmil
- 03R = 10.37 x 100 / 6530 = 0.1588 ohms
- 04Round-trip = 0.3177 ohms
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