Buying Compact Fluorescents

To select the right lamp for your application, check the wattage of the incandescent you are replacing. This table will give you a feel for what wattage compact fluorescent you will need to provide the same light output.

Remember this rule of thumb: a 3:1 ratio of incandescent to compact fluorescent wattage provides about the same light. Another approach is to read the lamp packages. Find the wattage incandescent lamp you would normally buy. Read the "lumen output" on the label. (Lumen is the measure of the lamp's light output.) Knowing that number, find a compact fluorescent labeled as producing about that many lumens. This method should assure you'll end up with a lamp that meets your lighting needs and saves you money.

Light Output Equivalency Table

Incandescent Fluorescent 
Bulb Wattage Bulb Wattage 
25w=7-9w  
40w=11w  
50-60w=13-14w  
60w=15-16w  
60-75w=17-18w  
60-75w=20w  
75-90w=22-23w  
75-100w=25-27w  
100w=28w  
100-120w=30-32w  
150w=38-39w  
175-225w=50-52w  
200-250w=55w  
250-300w=68-78w  


To order the right size compact fluorescent bulb, simply compare its measurements to the widest portion and the complete height (including the base or pin) of your existing bulb. Pay special attention to the measurement of the narrowest portion of your existing fixture, such as the narrow portion of the harp in a table lamp.