Enter the total power (watts) and the total time (s) into the calculator to determine the Energy from Watts. 

Energy from Watts Formula

The following equation is used to calculate the Energy from Watts. 

E = P(w) * T


  • Where E is the Energy from Watts (Joules)
  • P(w) is the total power (watts) 
  • T is the total time (s) 

How to Calculate Energy from Watts?

The following two example problems outline the steps and information needed in order to calculate the Energy from Watts.

Example Problem #1:

  1. First, determine the total power (watts). In this example, the total power (watts) is measured to be 85.
  2. Next, determine the total time (s). For this problem, the total time (s) is calculated to be 9.
  3. Finally, calculate the Energy from Watts using the formula above: 

E = P(w) * T

Inserting the values from above and solving the equation with the imputed values gives: 

E = 85 * 9 = 765 (Joules)

Example Problem #2: 

Using the same process as example problem 1, we first define the needed variables outlined by the formula. In this case, the values are provide as: 

total power (watts) = 9

total time (s) = 3

Entering these values into the formula or calculator above gives us: E = 9 * 3 = 27 (Joules)