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LED Series Resistor & Ohm's Law Calculator
Calculate the exact dropping resistance, select standard commercial E12/E24 resistor values, and evaluate thermal power dissipation with 2x safety derating.
LED Circuit Specifications
Typical standard indicators: 5-20 mA; Power LEDs: 350-700 mA
Recommended Resistor Values
Exact Resistance
-- Ω
R = (Vs - Vf) / If
Nearest Standard E24
-- Ω
Commercial 5% Resistor
Actual Current
-- mA
Power Dissipated
-- mW
Min Power Rating
1/4 W
Schematic Loop
Custom Engineering
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