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) 

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)