The Advanced Wire Size Calculator will calculate the proper wire size for a circuit based on circuit amps, preferred (or available) wire insulation, conductor type and installation specifications. This calculator also provides wire size correction factors for temperature, number of conductors in a raceway, and voltage drop for long wire runs.

Enter the information below to calculate the appropriate wire size.

For simpler circuits that do not need temperature or number of conductors correction factors, use the Wire Size Calculator.

For long conductor runs where voltage drop may be an issue, use the Voltage Drop Calculator to determine voltage drop and the Circuit Distance Calculator to determine maximum circuit length. Visit the Tables page to view reference tables such as Maximum Ampacity for Current-Carrying Conductors.

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