Electrical Calculators
Wire sizing, conduit fill, voltage drop, and service entrance calculations. Every result is NEC-referenced and ready for the field.
Tools built for the field
From quick wire-sizing lookups to NEC 220.82 service entrance calculations. Free to use, no account required to view.
Wire Size Calculator
Look up the minimum AWG wire size for a given ampacity per NEC Table 310.16.
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Conduit Fill Calculator
Calculate minimum conduit size and fill percentage per NEC Chapter 9.
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Voltage Drop Calculator
Calculate voltage drop and verify compliance with NEC 3% recommendation.
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Electrical Load Calculator
Calculate total electrical load in amperes from individual watt loads.
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Circuit Breaker Sizing
Size a circuit breaker for a load per NEC 240.4 and 210.20.
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Service Entrance Sizing
Size a residential service entrance per NEC 220.82 standard method.
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