Illuminance Converter – Lux, Footcandles & More

This illuminance unit converter routes every input through exact definitions — 1 footcandle = 10.7639104 lux exactly. Enter a value, pick the source and target units, and the result appears instantly with the factor applied shown beside it. Lux and footcandles quantify illuminance — how much light lands on a surface — with lux in lumens per square meter and the footcandle in lumens per square foot. The conversion mirrors the area factor exactly: 1 footcandle = 10.7639104 lux, because a square foot covers 0.09290304 m², so no measurement uncertainty enters the arithmetic. A mini table of the head factor makes spot-checks immediate: 1 fc = 10.7639 lux; 5 fc = 53.8196 lux; 10 fc = 107.6391 lux; 50 fc = 538.1955 lux; 100 fc = 1,076 lux. Office standards are written around 500 lux (about 46 fc), warehouses run 100–150 lux, and a bright overcast sky delivers about 1000 lux — anchors that reveal a missed factor of ten instantly.

1. 1

   Step 1

   Enter the value you want to convert

2. 2

   Step 2

   Select the source unit you are converting from

3. 3

   Step 3

   Select the target unit you want as the result

4. 4

   Step 4

   Read the exact result, then swap or copy as needed

• 1

  1 fc = 10.76 lux; memorize 50 fc ≈ 538 lux for offices

• 2

  Divide total lumens by area in m² for a first-pass lux estimate

• 3

  Standards: 300 lux reading, 500 lux office, 750 lux fine work

• 4

  Grow lights: leaf canopy wants 10,000–50,000 lux depending on plant

• Comparing lamp lumens to required lux without dividing by room area

• Using the 10.76 factor in the wrong direction between fc and lux

• Confusing illuminance (lux) with luminance (cd/m²) in screen specs