Illumination Converter
Convert illuminance: lux, foot-candle, phot.
1 lx = 0.092903 fc
About the illumination converter
Illuminance is the amount of light landing on a surface per unit area — what a light meter reads when you point it at a desk, sidewalk, or stage. The SI unit is the lux (lx), equal to one lumen per square meter; the imperial counterpart is the foot-candle (lumens per square foot). Building codes, photography apps, and horticulture growers all specify minimum lux levels for their tasks. Use this converter to move between lux, foot-candles, phot (cgs), and nox.
Frequently asked questions
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How many lux is a foot-candle?
One foot-candle equals about 10.764 lux. A 50-foot-candle office spec is therefore around 538 lux.
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What lux level do I need to read comfortably?
Around 300–500 lux is recommended for general reading and office work. Detailed tasks like drafting or sewing benefit from 750–1,500 lux.
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How bright is direct sunlight in lux?
Direct midday sun is about 100,000 lux. Overcast daylight is 1,000–10,000 lux, and a fully moonlit night is roughly 0.1–0.3 lux.