LED Series Resistor Calculator
About:
Use the calculator below to determine the series resistor needed to connect various series combinations of light emitting diodes or "LEDs". Use a resistor rated higher than the displayed power in the box below "Power (W)".
Choosing a resistor with twice the wattage rating is recommended to prevent it from getting hot.
Formula: R = (Vs - Vf) / If
Supply Voltage:
V
Forward Voltage:
V
Forward Current:
mA
Resistor Value:
Ω
=
Power:
W
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