## Lumens to lux calculator

Luminous flux in lumens (lm) to illuminance in lux (lx) calculator and how to calculate.

Enter the luminous flux in lumens, select area unit type, enter radius in meters for spherical light source or surface area

in square meters for any light source and press the

Calculatebutton to get the illuminance in lux:## Lumens to lux calculation formula

## Calculation with area in square feet

The illuminance

E_{v}in lux (lx) is equal to 10.76391 times the luminous fluxΦ_{V}in lumens (lm) divided by the surface areaAin square feet (ft^{2}):

E_{v(lx)}= 10.76391 ×Φ_{V(lm)}/A_{(ft}2_{)}

The illuminance

E_{v}in lux (lx) is equal to 10.76391 times the luminous fluxΦ_{V}in lumens (lm) divided by 4 times pi times the squared sphere radius r in feet (ft):

E_{v(lx)}= 10.76391 ×Φ_{V(lm)}/(4·π·r_{(ft)}^{2})

## Calculation with area in square meters

The illuminance

E_{v}in lux (lx) is equal to the luminous fluxΦ_{V}in lumens (lm) divided by the surface areaAin square meters (m^{2}):

E_{v(lx)}=Φ_{V(lm)}/A_{(m}2_{)}

The illuminance

E_{v}in lux (lx) is equal to the luminous fluxΦ_{V}in lumens (lm) divided by 4 times pi times the squared sphere radius r in meters (m):

E_{v(lx)}=Φ_{V(lm)}/(4·π·r^{2}_{(m}2_{)})

## See also