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LED Resistor Calculator

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Typical LED current is between 10mA - 20mA! Low power LED is 5mA - 10mA!
Consult your LED's datasheet before testing! If no datasheet is available, use ~20mA for initial testing.

Note: You should avoid connecting LEDs in parallel with just one resistor shared between them. Identical LEDs can be successfully connected in parallel, but each LED may have a slightly different voltage drop, and the brightness of the LEDs will differ. If you want to connect the LEDs in parallel each one should have its own resistor.

Color Voltage Drop
Red 2V
Green 3.2V
Blue 3.2V
White 3.2V
Yellow 2V
Orange 2V
Amber 2V

Cathode = Negative (Flat edge of LED)

Anode = Positive

Example Circuits