What is WATT?
Wattage is a unit of Electrical Work (power).
It's the amount of Electrical Energy removed from the circuit and consumed by the bulb.
Wattage is the rating unit used to measure total power consumption of bulb at a given voltage and amperage.
As wattage is directly related to voltage and amperage; a somewhat analogous description would be if a pipe containing water was connected to a water wheel, then the speed (pressure) of the water moving in the pipe would be the voltage, the volume (mass) of water moving through the pipe would be the amperage, and the total energy contained in the flow which turns the water wheel would be the wattage.
See Volt Amp Watt animations.
Published bulbs wattage rating is measured at the bulb's rated voltage.
Published specs for wattage typically have a tolerance of plus or minus 10%.
To calculate the wattage; if you know the voltage and amperage of the circuit, then wattage equals voltage times amperage (watt = volt x amp).
One Kilowatt is 1000 watts.
references for this page: WATT, KILOWATT, WATTAGE, WATTS
references to this page: AMP, CANDLEPOWER, CHARACTERISTIC CURVES, COLOR RENDERING INDEX, CONVERSION TABLE, FILAMENT, HALOGEN BULB, HOURS, INCANDESCENT BULB, LUMEN, LUMENS PER WATT, RE-RATE, VOLT, VOLT AMP WATT ANIMATIONS