Calculate Voltage, Current, Resistance & Power
Enter any two values to calculate voltage:
Ohm's Law is a fundamental principle in electrical engineering that describes the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. Named after German physicist Georg Ohm, this law states that the current through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance between them.
The fundamental equation is V = I × R, where V is voltage in volts, I is current in amperes, and R is resistance in ohms. This relationship can be rearranged to solve for any unknown variable when the other two are known.
Electrical power (P), measured in watts, can also be calculated using Ohm's Law relationships. Power equals voltage times current (P = V × I), or current squared times resistance (P = I² × R), or voltage squared divided by resistance (P = V² ÷ R).
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