Lux to Foot-Candles Converter

Lux and foot-candles measure illuminance, the amount of visible light arriving at a surface. Both describe luminous flux per unit area, so they represent the same physical quantity in different measurement systems. Lux is the SI unit and equals one lumen per square metre. A foot-candle is the customary unit used mainly in the United States and equals one lumen per square foot. Converting between them lets lighting plans, meter readings, and recommended light levels be compared consistently. One square metre contains approximately 10.7639 square feet. Because illuminance divides lumens by area, one foot-candle equals 10.7639104167 lux. To convert lux to foot-candles, divide by that factor. To convert foot-candles to lux, multiply by it. For example, 100 lux is approximately 9.290304 foot-candles, while 10 foot-candles is approximately 107.639104 lux. The calculator retains enough precision for practical lighting work and displays a concise result. Neither unit measures total lamp output. Lumens describe luminous flux emitted by a source, whereas lux and foot-candles describe the light reaching a particular plane. Illuminance changes with distance, beam direction, fixture optics, obstructions, and reflections. A lamp rated for many lumens can still produce low illuminance on a distant surface, while a focused fixture may create high illuminance over a small region. Measure at the actual task plane whenever working conditions matter. Typical applications include office lighting, photography studios, film sets, warehouses, retail displays, museums, horticulture, sports venues, and emergency egress. Standards may specify lux or foot-candles depending on the country and industry. Converting the units does not change the underlying measurement or imply that a recommended target has been met; it only changes how the same illuminance is expressed. For field measurements, place a calibrated light meter on the surface and orient its sensor as required by the standard. Avoid shading the sensor and account for daylight variation, fixture warm-up, and aging. Use this converter to translate the reading without rounding too early. For compliance or safety decisions, consult the relevant lighting code and preserve the instrument's stated uncertainty. The exact mathematical conversion is stable, but the quality of the final result always depends on the quality and location of the original measurement.