Luminous flux in lumens (lm) to electric power in watts (W) calculator.
Enter the luminous flux in lumens, luminous efficacy in lumens per watt and press the Calculate button to get the power in watts:
* the predefined luminous efficacy values are typical / average values.
Energy saving lamps have high luminous efficacy (more lumens per watt).
The power P in watts (W) is equal to the luminous flux ΦV in lumens (lm), divided by the luminous efficacy η in lumens per watt (lm/W):
P(W) = ΦV(lm) / η(lm/W)
| Lumens | Incandescent light bulb (watts) |
Fluorescent / LED (watts) |
|---|---|---|
| 375 lm | 25 W | 6.23 W |
| 600 lm | 40 W | 10 W |
| 900 lm | 60 W | 15 W |
| 1125 lm | 75 W | 18.75 W |
| 1500 lm | 100 W | 25 W |
| 2250 lm | 150 W | 37.5 W |
| 3000 lm | 200 W | 50 W |
