What is Color Rendering Index (CRI)?

The color rendering index is a way to quantify whether colors under a light source will look the same as in daylight. This is reflected (figuratively and literally) in the light source’s spectrum. A light source with a spectrum that is different than the sun will have a low color rendering index, while a light source with a similar spectrum to the sun will have a high color rendering index.  StellarNet’s LED Test Report Software and VBA-NIST- CRI/CQS program calculate CRI and Color Quality Scale (CQS) for different test light sources.