Every resistor has a limit to how much heat it can handle. This Power Dissipation Calculator uses Joule’s Law (P=I2⋅R) to determine exactly how many Watts your component will be forced to dissipate. Avoid “the magic smoke” by checking your wattage before you build.
Power Dissipation Calculator
Wattage Safety Margin: Never run a resistor at its maximum rated wattage. A good rule of thumb is to use a resistor rated for double the calculated power (e.g., if you calculate 0.1W, use a 0.25W resistor).
Airflow: In high-power applications, ensure your PCB has enough space around power resistors to allow for natural convection cooling.