Lumens to Watts Converter
Convert lumens to watts to estimate the power consumption of light sources based on their luminous efficacy. This tool is perfect for lighting designers, energy consultants, and anyone comparing energy efficiency across LED, incandescent, CFL, and other lighting technologies.
Convert Lumens to Watts Based on Luminous Efficacy
Lumens to Watts Conversion Formula
$$P = \frac{L}{\eta}$$
Where:
- $$P$$ — power in watts (W)
- $$L$$ — luminous flux in lumens (lm)
- $$\eta$$ — luminous efficacy in lumens per watt (lm/W)
This converter helps determine how much electrical power a light source consumes to produce a given luminous output. Luminous efficacy varies by light type:
- Incandescent bulb ≈ 10–17 lm/W
- CFL (Compact Fluorescent Lamp) ≈ 35–60 lm/W
- LED bulb ≈ 80–120 lm/W
By inputting the lumens and selecting a typical efficacy, you can estimate the wattage required — useful for comparing energy efficiency and planning lighting systems in homes, offices, or industrial settings.