Enter the voltage and resistance into the calculator to determine the headphone power. This calculator can also evaluate any of the variables given the others are known.

Headphone Power Formula

The following formula is used to calculate the power of headphones.

HP = V^2 / R


  • HP is the headphone power V is the voltage R is the resistance

To calculate the headphone power, square the voltage and then divide the result by the resistance.

What is a Headphone Power?

Headphone power refers to the amount of electrical energy that a pair of headphones requires to function and produce sound. It is typically measured in milliwatts (mW) and is directly related to the volume and quality of sound that the headphones can produce. The power is supplied by the device the headphones are connected to, such as a smartphone, computer, or audio amplifier. The higher the headphone power, the louder and clearer the sound can be, but too much power can potentially damage the headphones.

How to Calculate Headphone Power?

The following steps outline how to calculate the Headphone Power using the formula HP = V^2 / R.

  1. First, determine the voltage (V).
  2. Next, determine the resistance (R).
  3. Next, use the formula HP = V^2 / R to calculate the Headphone Power (HP).
  4. Finally, calculate the Headphone Power.
  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.

Voltage (V) = 12

Resistance (R) = 4