Ohm's Law Calculator
Enter any two of voltage, current and resistance and this Ohm's law calculator finds the third, plus power in watts.
Enter your values and press Calculate.
How to use the Ohm's Law calculator
Ohm's law describes how voltage, current and resistance relate in a simple resistive circuit. Leave the value you want to find blank.
Formula
V = I × R, I = V ÷ R, R = V ÷ I, P = V × I.
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