Ohm's Law Calculator

➔ Calculate Watts w/ Ohm's Law
➔ Calculate Amps w/ Ohm's Law
➔ Calculate Volts w/ Ohm's Law
➔ Calculate Ohms w/ Ohm's Law

Calculate Watts w/ Ohm's Law:

Enter any two of: E, I, and R
E:
I:
R:
Watts:

Calculate Amps w/ Ohm's Law:

Enter any two of: E, W, and R
E:
W:
R:
3-Phase:
Amperes:

Calculate Volts w/ Ohm's Law:

Enter any two of: W, I, and R
W:
I:
R:
Volts:

Calculate Ohms w/ Ohm's Law:

Enter any two of: E, I, and W
E:
I:
W:
Ohms:

An Ohm's Law Calculator is a tool that helps you quickly solve electrical equations based on Ohm's Law, which describes the relationship between voltage, current, resistance, and power in an electrical circuit.

Ohm's Law is expressed as:

V=I×R (Voltage = Current × Resistance)
From this, we can derive other formulas:

Watts (Power):
P=V×I
Amps (Current):
I=R/V
​
Volts (Voltage):
V=I×R
Ohms (Resistance):
R=I/V
​
The Ohm's Law Calculator simplifies these calculations — you just input the known values, and it calculates the missing one for you. It's super useful for electricians, engineers, students, and hobbyists working with electrical circuits.