Ohm’s Law Calculator

Voltage:

Current:

Resistance:

Power:

How to Use Ohm’s Law

If you know the current (I) and resistance (R), you can find voltage using: V=I×R

2. Calculate Current (I)

If you know the voltage (V) and resistance (R), you can find current using: I=V / R

3. Calculate Resistance (R)

If you know the voltage (V) and current (I), you can find resistance using: R=V / I

Power (P) in an electrical circuit is calculated using: P=V×I

Power can also be expressed in terms of resistance and current: P=I×I×R