As states have passed laws establishing charter schools, advocates have carefully tracked and analyzed state policies and enrollments to compare charter school growth, demand, and access across the United States. But to date, there have been no comparisons of charter school performance across states based on student achievement adjusting for background characteristics on a single set of nationally administered standardized tests, which can provide direct information about how much students are learning. This article provides that information, based on student performance in reading and math on the National Assessment of Educational Progress (NAEP) between 2009 and 2019. These rankings are adjusted for the age of the charter school and for individual students' background characteristics. Findings include: (1) students at schools run by charter networks outperform students at independent charters, on average, while students at schools run by for-profit organizations have lower scores on NAEP, on average; and (2) students at charters authorized by state education agencies have higher scores than students at those authorized by local school districts, noneducational organizations, or universities. It's hoped that these rankings will spur charter-school improvement in much the same way that NAEP results have stimulated efforts to improve student achievement more generally.