Lighting calculator
Lux to Watt Calculator
Estimate watts from lux, area, and luminous efficacy.
i First multiply lux × area to get lumens, then divide by efficacy.
Lighting calculator
Lux to Watt Calculator
Instant result
Result
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Enter values to calculate.
How to use
Follow these steps for a clear answer.
Enter the known values
Fill in the fields for your calculation.
Choose a mode if available
Use the tabs when multiple directions are offered.
Read the result
The result updates as you type.
Frequently asked questions
Key distinctions behind the calculation.
How does the Lux to Watt calculation work?
It uses the formula W = (lx × A) ÷ η = lm ÷ η.