Resistor calculator

LED resistor calculator

Choose your LED color:

LED’s Threshold Voltage (or click on LED color above)

Number of LED’s in serial

Eaches

Supply Voltage

LED current (watch the specification)

Calculate the Resistor:

Calculated resistance in Ohms

Rounded standard E12 value

Rounded Power using standart 5% resistor

Real current through the E12 resistor

Dissipated Power in the LED

Dissipated Power in the resistor

In the chart below you can click on the color fields to update the resistor colors and values.

4-Band Code

47 kΩ, 5%

470 kΩ, 1%

5-Band Code

Calculation Example