# Watts to lux calculator

## Watts to lux calculator

We are offering Electric power in watts (W) to illuminance in lux (lx) calculator to aid you in making calculations. Enter the value of power in watts, surface area measured in square feet / meters or the spherical radius in feet / meters and the value of luminous efficacy in lumens per watt, then hit the = button to get the illuminance in lux.

[Lightning_l_Watts_to_lux_calculator]

* the predefined luminous efficacy values can be called as the typical / average values.

## Watts to lux calculation formula

#### Watts to lux calculation with area in square feet

The value of the illuminance Ev in lux (lx) is apparently equal to 10.76391 times the value of power P in watts (W), multiplied by the luminous efficacy η measured in lumens per watt (lm/W) which is divided by the surface area A measured in square feet (ft2).

Ev(lx) = 10.76391 × P(W) × η(lm/W) / A(ft2)

#### Watts to lux calculation with area in square meters

The value of illuminance Ev measured in lux (lx) is apparently equal to the power P measured in watts (W), multiplied by the luminous efficacy η measured in lumens per watt (lm/W) divided by the surface area A in square meters (m2).

Ev(lx) = P(W) × η(lm/W) / A(m2)