An ideal spectral match for a solar simulator is based on the percentage of the integrated light intensity in 6 spectral ranges. A Class AAA solar simulator may not deviate more than 0.75 to 1.25 times the ideal percentage in each spectral range. Spectral match for an Oriel Sol3A with AM 1.5G spectral correction filter is shown to easily meet IEC, JIS, and ASTM Class A requirements.