Correlated Color Temperature (CCT) is a measure of the color of light emitted by a light source, measured in Kelvin (K). It indicates how "warm" or "cold" the light appears. The lower the CCT, the warmer the light, and the higher the CCT, the cooler the light.
For example:
- Warm white light (such as from incandescent bulbs) has a low CCT, usually between 2700K and 3000K. This light has a yellow or orange tint and is often associated with a cozy, intimate atmosphere.
- Neutral white light is between about 3500K and 4100K and has a more natural, less colored appearance.
- Cool white or daylight light has a higher CCT, usually between 5000K and 6500K, and has a bluish or whitish tint. This is often used in offices or environments where bright, energetic light is required.
CCT is therefore a useful measure to understand what a light source will look like in terms of colour temperature and can influence how a space or environment feels.