Compact Fluorescent Bulbs

Match the bulb base (e.g., screw or pin), physical shape to fit the fixture, and the wattage-equivalent and lumens needed for desired brightness; also confirm the fixture allows CFL use (some dimmers and enclosed fixtures require special rated CFLs)

CFLs are rated in lumens for brightness and color temperature in Kelvin; lower Kelvin (2700–3000K) is warm white, 3500–4100K is neutral, and 5000K+ is daylight. Expect CFL wattage to be much lower than an incandescent for the same lumen output

CFLs generally use about 60–80% less energy than incandescent bulbs and last thousands of hours, but actual savings depend on hours of use, startup frequency (frequent on/off shortens life), and local electricity rates

CFLs contain a small amount of mercury, so avoid breaking them; if a bulb breaks follow local guidance for cleanup and ventilation, and dispose of burned-out CFLs through household hazardous waste collection or local recycling programs that accept mercury-containing lamps

Only use CFLs labeled as dimmable with compatible dimmer circuits; many standard CFLs are incompatible with dimmers, timers, or some motion sensors and can flicker or have reduced lifespan unless specifically rated for those controls

Many CFLs take several seconds to reach full brightness and some models can flicker briefly at startup; choose instant-on or quick-start labeled CFLs for locations where immediate full light is important

Look for manufacturer warranties (typically listed in product details), reputable safety certifications (e.g., UL, ETL), clear lumen and Kelvin ratings, and an indicated rated life in hours to compare reliability across brands