Enter the input voltage (volts), the resistance of resistor 1 (ohms), and the resistance of resistor 2 (ohms) into the calculator to determine the Output Voltage. 

Output Voltage Formula

The following formula is used to calculate the Output Voltage.

Vo = Vi * R2 / (R1+R2)
  • Where Vo is the Output Voltage (volts)
  • Vi is the input voltage (volts) 
  • R1 is the resistance of resistor 1 (ohms) 
  • R2 is the resistance of resistor 2 (ohms) 

To calculate the output voltage, multiply the input voltage by the 1st resistance, then divide by the sum of both resistances.

How to Calculate Output Voltage?

The following example problems outline how to calculate the Output Voltage.

Example Problem #1

  1. First, determine the input voltage (volts). In this example, the input voltage (volts) is determined to be 140 .
  2. Next, determine the resistance of resistor 1 (ohms). For this problem, the resistance of resistor 1 (ohms) is measured to be 50 .
  3. Next, determine the resistance of resistor 2 (ohms). In this case, the resistance of resistor 2 (ohms) is found to be 4.
  4. Finally, calculate the Output Voltage using the formula above: 

Vo = Vi * R2 / (R1+R2)

Inserting the values from above into the equation gives: 

Vo = 140 * 50 / (50+4) = 129.62 (volts)

Example Problem #2

Using the same method as above, determine the variables required by the equation. For this example problem, these are provided as follows: 

input voltage (volts) = 301

resistance of resistor 1 (ohms) = 4

resistance of resistor 2 (ohms) = 34

Entering these given values into the calculator above yields:

Vo = 301 * 4 / (4+34) = 31.68 (volts)