Electrical
Electrical Ohm's Law Calculator
Solve for voltage, current, resistance or power from any two of them.
Result
Ohm's law describes a resistive DC circuit. AC circuits with motors, transformers or electronics have reactance as well as resistance, so current and voltage fall out of step and the simple product overstates real power.
Get a Free Business AuditQuestions
About this calculator
Does this work for AC?
For purely resistive AC loads, yes. Anything inductive or capacitive needs impedance and power factor rather than plain resistance.
Why does resistance rise when things get hot?
For most metals it does, roughly linearly. It is why a lamp filament measures far lower resistance cold than it shows in operation.
The formula
V = I x R; P = V x I; and the rearrangements of both
Put this calculator on your site
Free to embed. Paste this where you want it to appear. It stays up to date automatically because it loads from BDEVY.
Please keep the attribution line. It is the only thing we ask in return.
Estimating is the easy part
The jobs you never hear about cost more than the ones you mis-measure. BDEVY builds the marketing, systems and automation that bring them in.