Enter the real power and power factor into the calculator to determine the apparent power. This calculator can also evaluate any of the variables given the others are known.

Watts To Va Formula

The following formula is used to calculate the apparent power in volt-amps (VA) from real power in watts (W) and power factor (PF).

VA = W / PF

Variables:

  • VA is the apparent power (volt-amps) W is the real power (watts) PF is the power factor (unitless, between 0 and 1)

To calculate the apparent power in volt-amps, divide the real power in watts by the power factor. The power factor is a unitless number between 0 and 1 that represents the ratio of the real power that is used to do work and the apparent power that is supplied to the circuit.

What is a Watts To Va?

Watts (W) and Volt-Amps (VA) are both units of measurement for electrical power. However, they represent different aspects of power. Watts measure the real power, which is the actual power used to do work or the power dissipated in a circuit. On the other hand, VA measures the apparent power, which is the product of voltage and current in a circuit. The difference between the two is due to the phase difference between the voltage and current in AC circuits. Therefore, the conversion from Watts to VA depends on the power factor of the circuit.

How to Calculate Watts To Va?

The following steps outline how to calculate the Watts To VA using the formula: VA = W / PF.


  1. First, determine the real power (W) in watts.
  2. Next, determine the power factor (PF) as a unitless value between 0 and 1.
  3. Next, use the formula VA = W / PF to calculate the apparent power (VA) in volt-amps.
  4. Finally, calculate the Watts To VA.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

real power (W) = 120

power factor (PF) = 0.8