Enter the total lux (lx) and the total power (watts) into the Calculator. The calculator will evaluate the Lux Per Watt. 

Lux Per Watt Formula

LPW = L / W


  • LPW is the Lux Per Watt (lux/watt)
  • L is the total lux (lx)
  • W is the total power (watts)

To calculate Lux Per Watt, divide the total lux by the power in watts.

How to Calculate Lux Per Watt?

The following steps outline how to calculate the Lux Per Watt.

  1. First, determine the total lux (lx). 
  2. Next, determine the total power (watts). 
  3. Next, gather the formula from above = LPW = L / W.
  4. Finally, calculate the Lux Per Watt.
  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.

total lux (lx) = 50

total power (watts) = 40