Electrical
Ohm's Law Calculator
Solve any part of Ohm's law (voltage, current, resistance or power) from the two values you know.
Result
Electrical work is life-safety work governed by the NEC or your local code, and must be designed and installed by a licensed electrician. Conductor and overcurrent sizing depends on ambient temperature, conductor bundling, termination ratings, continuous-load rules and more. This is an educational estimate and must never be used as the basis for an installation. Ohm's law applies to purely resistive DC circuits. AC circuits with motors or electronics have reactance and a power factor that this does not model.
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About this calculator
What is Ohm's law?
Voltage equals current times resistance. Rearranged, current is voltage divided by resistance, and resistance is voltage divided by current. Power is voltage times current.
Why doesn't this match my AC motor?
Motors are inductive, so current and voltage are out of phase and apparent power exceeds real power. You need the power factor to work with AC motor loads properly.
The formula
V = I × R; P = V × I
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