highCRI

HighCRI, short for high color rendering index, refers to lighting sources whose colors appear more faithful to a reference illuminant under the same correlated color temperature. CRI is a standardized metric on a 0–100 scale, with 100 representing perfect color fidelity. The most commonly reported value is Ra, the average of eight standard test colors (R1–R8); some editions include R9 for saturated red to gauge red color rendering.

High-CRI is typically defined as Ra of 90 or greater; values 95+ are considered excellent and are often used in color-critical settings such as art galleries, photography studios, and retail displays where accurate color perception is important. LED technologies have enabled high-CRI performance across a variety of CCTs, but CRI has limitations as a sole measure of color quality. It may not reflect rendering of saturated colors in all conditions, and it does not capture metameric differences or perceptual effects across the full spectrum.

CRI’s limitations arise from its reliance on a fixed set of test colors and from prioritizing fidelity over other perceptual aspects. Because the metric is influenced by correlated color temperature and observer adaptation, two light sources with similar Ra values can render colors differently in practice.

Newer metrics such as TM-30-15 provide a more comprehensive assessment by using 99 color samples and reporting fidelity (Rf) and gamut (Rg) to describe color rendering and color-saturation changes. In practice, professionals may use CRI alongside TM-30 metrics to evaluate color quality, especially in applications where accurate color perception is essential.