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Lux to Footcandle Converter

Convert illuminance between lux and foot-candles in either direction, with kilolux and real-world light-level references for context.

Lux to Footcandle Converter

Enter a non-negative illuminance in lux to convert to foot-candles.

500 lux equals

46.4515 foot-candles

Lux

500 lx

Foot-candles

46.4515 fc

Kilolux

0.5 klx

For context: 500 lux is roughly an office desk at recommended task lighting (about 500 lux, 46 fc).

Office task range: 300 to 750 lux (28 to 70 fc) covers general office and reading work. Most desk standards target about 500 lux (46 fc) on the work surface.

1 fc = 10.76391 lux. 1 lux = 0.0929 fc. Mental shortcut: divide lux by about 10.76 to get foot-candles, or multiply foot-candles by about 10.76 to get lux.

Frequently Asked Questions about the Lux to Footcandle Converter

How do you convert lux to foot-candles?
Divide the lux value by 10.76391 to get foot-candles, since one foot-candle equals 10.76391 lux. For example, 500 lux divided by 10.76391 is about 46.45 foot-candles. To go the other way, multiply foot-candles by 10.76391 to get lux.
Why is one foot-candle equal to 10.76391 lux?
Both units measure luminous flux per unit area: one lux is one lumen per square meter, and one foot-candle is one lumen per square foot. Because one square foot equals 0.09290304 square meters exactly, spreading the same lumen over a square meter gives 1 divided by 0.09290304, which is about 10.76391. So one foot-candle of light is 10.76391 times as intense as one lux.
What is the difference between lux and foot-candles?
They measure the same thing, illuminance, but use different reference areas. Lux is the SI unit (lumens per square meter) and is standard in most of the world, while foot-candles (lumens per square foot) are common in United States lighting design and older fixtures. A reading in one unit can always be restated in the other using the 10.76391 factor.
How many lux or foot-candles do I need for an office desk?
General office and reading tasks typically call for 300 to 750 lux, which is about 28 to 70 foot-candles, with around 500 lux (46 foot-candles) a common target on the work surface. Detailed or precision tasks need more, while corridors and storage areas can use much less. Check the relevant standard, such as IESNA recommendations or EN 12464-1, for your exact task.
Does this converter account for distance or lamp brightness?
No. It only restates one already-measured illuminance value in the other unit. It does not apply the inverse-square law, lamp lumens, beam angle, or surface reflectance, so you still need a light meter or a separate lighting calculation to find the illuminance at a given point.
What light levels do typical foot-candle values represent?
A dim hallway is roughly 5 foot-candles (50 lux), a comfortable living room about 14 foot-candles (150 lux), and an office desk near 46 foot-candles (500 lux). An overcast day is around 93 foot-candles (1,000 lux), while direct midday sun reaches about 11,000 foot-candles (120,000 lux).

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