LED Resistor Calculator

Find the right current-limiting resistor for your LED. Don't fry it.

// don't fry your LED — pick the right current-limiting resistor

typical: 10–20 mA for standard LEDs; 1–5 mA for indicators

Exact Resistor
150 Ω
Nearest E24 Standard
150 Ω
Actual Current (with E24)
20.0mA
Resistor Power
60.0mW
▸ show formula
R = (Vsupply − Vf) / I
Vf = LED forward voltage, I = desired current in amps
LEDresistorforward voltagecurrent limiting