 This paper examined the accuracy of Landsat 8OLI's reflectance-based calibration results against ground-based measurements. The results showed that OLI was accurate to within plus or minus 2% in most bands when compared to the ground-based measurements. Additionally, the results from the tandem Landsat 7 and 8 flights indicated that OLI agreed with ETM plus to within plus or minus 2%. This article was authored by Jeffrey Zapplemires, Joel McCorkle, Nicolaus Anderson, and others.