Resistor Power Rating Calculator

This calculator uses two equations that are important for designing electronics:

Ohm’s Law

$$V = I \times R$$

and the Power Equation

$$P = I \times V$$

A simple use of these is finding the power rating required for resistors. In this case, enter any two of the following values: the voltage across the resistor, the current through the resistor, or its resistance in ohms to find the power dissipation in watts. This is the minimum power rating you can use on your resistor. Our calculator rounds up to the nearest value to ensure minimum safety.

Circuit Values
Please enter any two of the following three values for your circuit
Resistance value of resistor
Voltage across your resistor
Current through your resistor in milliamps
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