Illuminance Converter
Convert lux, footcandles, kilolux and phot for the same measured incident light.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Normalize incident luminous flux per area to lux, or lumens per square meter.
1 footcandle=1 lm/ft²=1/(0.3048²) lux
Worked example
100 footcandles is approximately 1076.39104 lux. One lux is one lumen per square meter.
Assumptions and input details
Illuminance describes light incident on an area, not a lamp’s total lumens or a surface’s luminance in nits. This unit conversion does not infer room geometry, beam angle, distance, exposure, lighting adequacy or a recommended light level.
References: NIST Guide to the SI: conversion factors
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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