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Wire Size & Conduit Fill Calculator

Find the correct AWG wire for your load, check voltage drop over distance, and calculate conduit fill percentage per NEC Chapter 9.

Wire Size by Ampacity — NEC 310.15(B)(16)

LOAD AMPS (A)

WIRE MATERIAL

TEMPERATURE RATING

AMBIENT TEMPERATURE

NUMBER OF CURRENT-CARRYING CONDUCTORS IN CONDUIT

3 or fewer — no derating (1.00×) 4–6 conductors — derate to 80% (0.80×) 7–9 conductors — derate to 70% (0.70×) 10–20 conductors — derate to 50% (0.50×)

⚡ RESULTS

Voltage Drop Calculator

LOAD AMPS (A)

ONE-WAY DISTANCE (feet)

SYSTEM VOLTAGE

PHASE

WIRE MATERIAL

WIRE SIZE (AWG / MCM)

⚡ RESULTS

Conduit Fill Calculator — NEC Chapter 9, Table 1

CONDUIT TYPE

CONDUIT TRADE SIZE

CONDUCTORS

⚡ RESULTS

NEC Ampacity Reference — NEC 310.15(B)(16)

AWG / MCM	Cu 60°C (A)	Cu 75°C (A)	Cu 90°C (A)	Al 60°C (A)	Al 75°C (A)	Al 90°C (A)

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