Ohm's Law Calculator
Enter any two of Voltage, Current, Resistance, or Power to calculate the remaining values.
Ohm's Law Results
What is the Ohm's Law Calculator?
The Ohm's Law Calculator solves for voltage, current, resistance, and power in DC electrical circuits. By entering any two known values, the calculator determines the other two and displays the formulas used.
How to Use
- Enter exactly two known values into any of the four input fields.
- Leave the other two fields blank.
- Click Calculate to see the solved values and the formulas applied.
Frequently Asked Questions
What is Ohm's Law?
Ohm's Law states that voltage (V) equals current (I) multiplied by resistance (R): V = I × R. It is the fundamental relationship used to analyze simple electrical circuits.
How is power calculated?
Power (P) in watts is calculated as P = V × I. It can also be expressed as P = I² × R or P = V² / R depending on which values are known.
What happens if I enter more than two values?
The calculator requires exactly two inputs to avoid contradictions. If more than two fields have values, it will ask you to clear the extras.
Does this work for AC circuits?
This calculator uses the basic DC Ohm's Law. For AC circuits with reactive components, impedance and phase angle must also be considered.