What is Kelvin?

The Kelvin definition is the SI base unit of thermodynamic temperature, equal in magnitude to the degree Celsius. Scientific jargon aside, Kelvin is used in lighting to measure the color temperature of a particular light bulb. And in short, the higher the Kelvin rating (typically expressed in K), the whiter the lighting will be.

How to Choose The Right Kelvin Color Temperature

Light bulb color temperature is represented in the unit of absolute temperature, Kelvin, noted by the symbol K. Household fixtures are commonly found in color temperatures on the Kelvin scale of 2700K (warm incandescent), 3000K (warm white halogen) and 3500K (household fluorescent). Color temperatures higher than 3500K are typically used for commercial and hospital applications, as the light is bright with a bluish daylight cast that can be harsh for home interiors; but task lighting may be useful at 4000K and above. When selecting new lighting for your home, be sure to take into account its color temperature to ensure you're making the right choice.

Color Temperature Chart

The right color temperature begins with the bulb. Use the Kelvin temperature color scale below to help identify the approximate hue certain bulbs will provide.

Kelvin Color Temperature Scale

Color Temperatures of Light Bulbs

Aside from the light bulb itself, use Kelvin temperature can also help guide you in determining which fixture is right for each room. Whether you need an ambient source of light or one for highly-focused task lighting, keep in mind the following Kelvin ranges:

  • Less than 2000K: gives off a dim glow of light, similar to what you might find from candlelight; best for low light areas where ambient illumination is welcomed
  • 2000K-3000K: gives off a soft white glow, often yellow in appearance; best for living rooms, dining rooms, bedrooms and outdoor spaces
  • 3100K-4500K: gives off a bright amount of white light; best for kitchens, offices, work spaces and vanities where task lighting is needed
  • 4600K-6500K: gives off a bright amount of blue-white light, similar to that of daylight; best for display areas and work environments where very bright illumination is needed
  • 6500K and up: gives off a bright bluish hue of light, often found in commercial locations; best for bright task lighting

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