Lumens to Watts Calculator

Your details

Switch between lumens-to-watts and watts-to-lumens conversion.
The luminous flux output of the bulb in lumens. Check the bulb packaging.
lm
Efficacy midpoints are DOE typical values. Choose "Custom" to enter an exact lm/W.
Scale the result for a fixture or room with multiple identical bulbs.
Used to estimate daily and yearly energy use. Leave at 0 to skip the energy breakdown.
hr/day
Power per bulbHighly efficient
8.89W

Wattage required to produce the entered lumens with the chosen bulb type

Brightness per bulb800lm
Luminous efficacy used90lm/W
Total power (all bulbs)8.89W
Daily energy use0.044kWh/day
Yearly energy use16.22kWh/yr
90 lm/W
Very inefficient<16Low efficiency16-40Moderate efficiency40-80High efficiency80-120Very high efficiency120+

800 lumens requires approximately 8.9 watts.

  • At 90 lm/W this is among the most efficient bulb types available. LEDs typically reach 80-120 lm/W.
  • Running these for 5 hours a day uses about 16.22 kWh per year.

Next stepFor the most accurate result, use the lm/W figure printed on your bulb packaging rather than the bulb-type preset.

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