Lux to candela

Lux to candela: use illuminance, distance. Review the formula, worked example and calculation steps.

Inputs

Use the units shown
RESULT
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Enter your values and select Calculate.

Formula & explanation
I = E × d²

Variables & units

Illuminance
lx · minimum 0, maximum 1000000000000
Distance
m · minimum 0.000001, maximum 1000000000000

Worked example

Change the supplied example values to match your circuit.

Assumptions

Uniform flux over the supplied area or cone. Distance assumes a point source and normal incidence. Supply the actual efficacy of your light.

Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.

Practice with an example

Use the default input values to find the answer. The reset icon restores those values.

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