The LED Series Resistor Calculator is a tool that assists in finding the right resistor value for connecting an LED to a power source without causing damage. This resistor serves to regulate the current flowing through the LED.

To figure out the appropriate series resistor value for an LED, you usually need to know three key things:

**Supply voltage (V_s):**This is the power source’s voltage, such as that of a battery.**LED forward voltage (V_f):**The specific voltage drop across the LED.**LED forward current (I_f):**The desired current to pass through the LED.

The general formula to calculate the series resistor for an LED is:

**R = (V_s - V_f) / I_f**

Here:

**R**represents the resistance value in ohms (Î©).**V_s**stands for the supply voltage.**V_f**is the LED’s forward voltage.**I_f**denotes the LED’s forward current.