CCT determines how yellow or blue the hue of the light emitted from a bulb or fixture is. CCT is measured in the unit Kelvin (K) and most commonly can vary anywhere from 2000K to 6500K for residential applications. With LEDs, you have the ability to pick from many CCTs, whereas traditional light sources had limited choices. Traditionally most incandescents had a warm hue and a low CCT.
Warm White (soft white) bulbs and fixtures have a low CCT, around 2000K-3500K, and feature a more yellow/orange hue. Natural White (bright white) bulbs or fixtures have an average CCT, around 3600K-5000K, and feature a neutral white hue. Lastly, Cool White (daylight) bulbs or fixtures have a high CCT, around 5100K-6500K, and feature a blue/white hue.
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