Conductor Resistance Temperature Calculator

Use this resistance-temperature workflow when you already know the conductor resistance basis and coefficient. It does not identify conductor material or select wire size.

  • Updated August 22, 2026
Inputs
Result

Formulas

  • Temperature change = operating temperature - base temperature
  • Adjusted resistance = base resistance x (1 + coefficient x temperature change)
  • Percent change = (adjusted resistance / base resistance - 1) x 100

Use this calculator

Estimate conductor resistance at a new temperature from base resistance, temperatures, and a temperature coefficient.

Read the result

Review the calculated values with their displayed units and assumptions. The result is a planning aid for the stated inputs, not a final equipment or installation decision.

Check before final work

This resistance-temperature estimate uses a user-supplied linear coefficient. It does not identify material, replace verified conductor data, select a wire, or determine code compliance.

FAQs

Where does the coefficient come from?

Use a verified coefficient for the conductor material and temperature range you are evaluating. This calculator does not look up that value.

Can this select AWG or kcmil?

No. It adjusts a resistance value you provide and does not select conductor size or ampacity.