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Illuminance in Lux & Foot-Candles

Convert nonnegative illuminance between lumens per square meter and lumens per square foot.

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Enter the known values in the units shown. Results update as you type.
Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
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100 foot-candles equals about 1,076.391 lux. Exactly 1 lux equals 0.09290304 foot-candles.

Lux = foot-candles / 0.09290304

Enter these known values and leave the other values blank.

Both fields represent the same nonnegative illuminance. One foot-candle is one lumen per square international foot; one lux is one lumen per square meter.
This converts an existing illuminance value. It does not infer illuminance from lamp lumens without illuminated area and distribution.
Illuminance is incident light on a surface. It is different from luminous intensity in candela and luminance in candela per square meter.

No. They measure illuminance. The foot in the name comes from the square-foot area used in the unit definition.

Yes. Zero lux and zero foot-candles represent the same zero illuminance.

Bookify requires nonnegative illuminance. Foot-candles use the exact international square foot rather than the rounded captured illuminance factor.