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 Calculate button to get the illuminance in lux:

Enter luminous flux in lumens:		lm
Select area unit type:	Area in square feet Area in square meters
Enter spherical radius:
Or enter surface area:
Illuminance result in lux:		lx

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