A 100-watt incandescent bulb gives off 1,600 lumens. Watts measure the electrical energy required to light a bulb, while lumens are a measure of the brightness of the light produced.
Energy-saving bulbs such as compact fluorescent lamps and LED bulbs that produce an equivalent lumens as the 100-watt incandescent bulb use only 24 to 25 watts of energy. These bulbs also last longer, allowing users to save more on energy costs. To help consumers buy CFLs and LED bulbs, the Federal Trade Commission and manufacturers have worked together to create new labels for these bulbs. Indicated in the labels are the bulbs' brightness in lumens, life expectancy, watts used and light appearance. This makes it easy for consumers to buy energy-saving replacement bulbs for their old incandescent bulbs.