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Learn About Light Output

Parts of a CFL

You can find the brightness in lumens right on the front of the package.
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Brightness is a description of light output, which is measured in lumens (not watts). Light bulb manufacturers include this information and the equivalent wattage right on the packaging. Common terms are "soft white 60," "warm light 60," and "60 watt replacement." Sometimes a diagram will show two images with an equal sign, as in the packaging image to the right.

To save energy, find the bulbs with the light output you need, and then choose the one with the lowest wattage. You can also look for an ENERGY STAR certified bulb that is labeled as equivalent to the incandescent bulb you are replacing.

The color of light may also affect how bright a light appears, even if the lumens are the same. Since most people are used to the soft yellowish glow from incandescent light bulbs, ENERGY STAR certified bulbs that produce light closer to the color of daylight (color temperatures above 3000K) may appear brighter because the color of the light is less yellow. Learn more about color temperature.

How Much Light Do I Need?

Old Incandescent Bulbs
ENERGY STAR Bulb Brightness
(Minimum Lumens)
40 450
60 800
75 1,100
100 1,600
150 2,600