Conductor Resistance at Temperature

Resistance of copper or aluminum at temperature.

Example

You enter

You get

Details, formula, and sources

R(T) = R(20°C) × (1 + α × (T − 20°C)); α copper = 3.93 × 10⁻³ /K; α aluminum = 4.03 × 10⁻³ /K.

CRC Handbook material properties; NIST temperature-coefficient values.

NIST data free at nist.gov; CRC Handbook by name.

Estimate. AHJ and licensed electrician govern. Verify against the NEC edition adopted in your jurisdiction.

Field names used by the API: material, awg, length_ft, temperature_C, resistance_ohm, resistance_ohm_per_kft

Details, formula, and sources

R(T) = R(20°C) × (1 + α × (T − 20°C)); α copper = 3.93 × 10⁻³ /K; α aluminum = 4.03 × 10⁻³ /K.

CRC Handbook material properties; NIST temperature-coefficient values.

NIST data free at nist.gov; CRC Handbook by name.

Estimate. AHJ and licensed electrician govern. Verify against the NEC edition adopted in your jurisdiction.