WireSizing
Wire gauge reference & calculator

Wire Conductor Materials

Properties of common conductor materials. Resistivity determines how much a wire resists current flow; density affects weight; the temperature coefficient shows how resistance changes with heat.

Copper (Cu)

The standard conductor for electrical wiring. Excellent conductivity, ductility, and corrosion resistance.

Resistivity: 1.72e-08 Ω·m
Density: 8,960 kg/m³
Temp coeff: 0.00393/°C

Aluminum (Al)

Lighter and cheaper than copper but requires larger gauge for equivalent ampacity. Common in utility and feeder applications.

Resistivity: 2.65e-08 Ω·m
Density: 2,700 kg/m³
Temp coeff: 0.00429/°C

Silver (Ag)

Highest electrical conductivity of any metal. Used in specialized high-performance applications.

Resistivity: 1.59e-08 Ω·m
Density: 10,490 kg/m³
Temp coeff: 0.0038/°C

Gold (Au)

Excellent corrosion resistance and reliable contact properties. Used for connectors and thin plating.

Resistivity: 2.44e-08 Ω·m
Density: 19,300 kg/m³
Temp coeff: 0.0034/°C

Nickel (Ni)

High-temperature resistance and corrosion resistance. Used in thermocouples and heating elements.

Resistivity: 6.99e-08 Ω·m
Density: 8,900 kg/m³
Temp coeff: 0.006/°C

Nichrome (NiCr)

Nickel-chromium alloy with very high resistance. The standard material for heating elements.

Resistivity: 1.10e-06 Ω·m
Density: 8,400 kg/m³
Temp coeff: 0.0004/°C

Steel (Fe)

High tensile strength but poor conductivity. Used where mechanical strength matters more than electrical performance.

Resistivity: 1.43e-07 Ω·m
Density: 7,850 kg/m³
Temp coeff: 0.005/°C

Tinned Copper (Sn-Cu)

Copper wire coated with tin for improved corrosion resistance. Standard for marine and harsh environments.

Resistivity: 1.78e-08 Ω·m
Density: 8,900 kg/m³
Temp coeff: 0.00393/°C