Enter the power and the product of the area and luminous efficacy into the calculator to determine the illuminance. This calculator can also evaluate any of the variables given the others are known.

Watts To Lux Formula

The following formula is used to calculate the conversion from Watts to Lux.

L = W / (A * E)

Variables:

  • L is the illuminance in Lux (lx)
  • W is the power in Watts (W)
  • A is the area in square meters (m²)
  • E is the luminous efficacy in lumens per watt (lm/W)

To calculate the illuminance in Lux, divide the power in Watts by the product of the area in square meters and the luminous efficacy in lumens per watt. This will give the amount of light that falls on a certain area per unit of power consumed.

What is Watts To Lux?

Watts to Lux is a conversion used in lighting to measure the intensity of light. Watts is a unit of power that measures the rate of energy conversion or transfer, typically used to express the output power of engines and the power consumption of tools and machines. Lux, on the other hand, is a unit of illuminance that measures the amount of light that falls on a certain area. Therefore, converting Watts to Lux helps to understand how much light is produced per unit of power consumed.

How to Calculate Watts To Lux?

The following steps outline how to calculate the Watts To Lux using the given formula:


  1. First, determine the power in Watts (W).
  2. Next, determine the area in square meters (m²).
  3. Next, determine the luminous efficacy in lumens per watt (lm/W).
  4. Next, gather the formula from above = L = W / (A * E).
  5. Finally, calculate the illuminance in Lux (lx).
  6. 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:

power in Watts (W) = 50

area in square meters (m²) = 10

luminous efficacy in lumens per watt (lm/W) = 20