LEDs
LED Resistor Calculator
Enter supply voltage, LED forward voltage, and target current — get the exact resistor value, the nearest E12 standard value, and LED power dissipation.
Resistor
150 Ω
Nearest E12: 150 Ω → ~20.0 mA actual
Power dissipation
60.0 mW
A 1/4 W (250 mW) resistor is safe up to ~125 mW. LED dissipates 40.0 mW.
R = (Vs − Vf) / I_LED
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