In the past, watts were the primary means to measure the “brightness” of an incandescent light bulb, based on the overall energy used to power it. Now, however, with energy-efficient lighting options like LED and CFL, Watts are not a consistent measurement tool in relation to brightness. LED and CFL bulbs can use up to 85% less energy to replicate the same level of brightness, measured in lumens, that we experienced with incandescent light bulbs.
For example, a typical 60-watt incandescent bulb produces 800 lumens of light output. A 15-watt CFL or a 12-watt LED can produce the same lumen output! In the past, a drastic change in wattage would have resulted in an equally drastic change in lumens. Today, lumens can vary greatly without having to increase the energy used to power a light bulb.
Now, rather than reviewing different watt ratings for your bulb and fixture, it is more important to consider the lumens, or brightness of the bulb, in relation to the area you want to illuminate.