Calculate voltage, current, resistance, and power using Ohm’s Law when you know two of the quantities.
The Ohm’s Law calculator calculates the voltage, current, resistance, and power in an electrical circuit when you know two of these quantities. Ohm’s Law connects voltage, current, and resistance: U = R × I.
The calculator is free, works in your browser without registration, and shows the result as soon as you change the values. The calculation is done on your device, and the information you enter is not sent anywhere.
U = R × I, P = U × I. From these, we also get I = U / R, R = U / I, P = I² × R, and P = U² / R.
A voltage of 230 volts and a resistance of 46 ohms give a current of 5 A and a power of 1,150 W. With default values, the calculator gives the result: Result 230.000 V · 5.000 A.
For electrical engineering students, hobbyists, and anyone who wants to size a circuit or device.
Ohm's Law states that the current through a conductor is directly proportional to the voltage: U = R × I.
Power (watt) indicates how much energy is consumed per second: P = U × I.
This calculator assumes a resistive load with a power factor of 1. In other cases, the results are indicative.