LED Series Resistor Calculator

Calculate the series resistor for one or several LEDs in series. Enter Supply Voltage, LED forward voltage, desired LED current and number of LEDs. Leave all fields filled and press Calculate.

LED Series Resistor Calculator





Typical forward voltages (single LED):

LED Type Typical Vf
Infrared (IR) ~1.2 V
Red / Orange ~1.8 – 2.2 V
Yellow ~2.0 V
Green ~2.0 – 3.0 V
Blue / White ~3.0 – 3.6 V