Lux to Watts Calculator
Convert illuminance (lux), area and efficacy to power (watts).
Input Data
Input Illuminance E.
lx
Input Area A.
m²
Input Luminous efficacy η.
lm/W
Results
30W
P = E × A / η = 300 lx × 10 m² / 100 lm/W = 30.000000 W
At a glance:Lux to Watts Calculator: enter parameters to compute results; complements related calculators.
Formula
P = E × A / η
E: illuminance (lx), A: area (m²), η: luminous efficacy (lm/W)
How to Use
- Enter illuminance E (lux).
- Enter area A (m²).
- Enter luminous efficacy η (lm/W).
- Get power P (watts).
Case Studies
E = 100 lx, A = 10 m², η = 100 lm/W
P = 100 × 10 / 100 = 10 W.
FAQ
Where from?
Φ = E·A then P = Φ/η combine to P = E·A/η.
How to save?
Raise η or lower target illuminance to cut power.
Related Tools
References
Content review: Calculatorism Science Team. Formula and numeric tests verified; results for reference only.