JobVolt
V = I·R · free web tool

Ohm's Law Calculator

Enter any two values and get the other two. Voltage, current, resistance and power, solved with V = I × R and P = V × I, with every derived value shown.

I know
VoltageV
CurrentA
Result
7.5 ΩResistance
Voltage120 V
Current16 A
Resistance7.5 Ω
Power1920 W
How this was determined
Ohm’s lawV = I × R
PowerP = V × I
Derived resistance7.5 Ω
Derived power1920 W

Take this math to the job site.

The JobVolt app runs the same verified engines offline, keeps every calculation in History, and turns them into inspector-ready PDF submittals on your letterhead.

Download on the App StoreGet it on Google Play

The wheel, without the wheel

Every combination reduces to two identities: V = I × R and P = V × I. From any two known values the calculator derives the rest and shows which ones were computed. Resistive load is assumed; for motors and reactive loads, power factor changes the picture and the app handles it.