How this calculator works
Lux and footcandle measure illuminance, not source power or luminance. A footcandle is one lumen falling on one square foot. Since an international foot is exactly 0.3048 m, a square foot is exactly 0.09290304 m2. Changing units leaves the physical lighting level unchanged.
Formula
1 fc = 1/0.09290304 lx = 10.7639104167 lx; fc = lx × 0.09290304.
Worked example
100 lx equals 9.290304 fc. Conversely, 1 fc equals approximately 10.7639104 lx.
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Frequently asked questions
Is footcandle a unit of distance?
No. Despite its name, it measures illuminance over an area.
Is lux the same as lumens?
Lumens measure light flux. Lux measures lumens received per square metre.
Is the conversion exact?
The area conversion is exact. A displayed decimal approximation can be rounded.