Watts to Lumens Calculator
Convert power (watts) and luminous efficacy to luminous flux (lumens).
Input Data
Input Power P.
W
Input Luminous efficacy η.
lm/W
Results
800lm
Φ = P × η = 8 W × 100 lm/W = 800.000000 lm
At a glance:Watts to Lumens Calculator: enter parameters to compute results; complements related calculators.
Formula
Φ = P × η
P: power (W), η: luminous efficacy (lm/W), Φ: luminous flux (lm)
How to Use
- Enter power P (watts).
- Enter luminous efficacy η (lm/W).
- Get luminous flux Φ (lumens).
Case Studies
P = 8 W, η = 100 lm/W
Φ = 8 × 100 = 800 lm.
FAQ
Vs lumens-to-watts?
It is the inverse: Φ = P·η.
Old bulbs?
Incandescents are ~10–15 lm/W, far below LEDs.
Related Tools
References
Content review: Calculatorism Science Team. Formula and numeric tests verified; results for reference only.