Internationally comparable test scores play a central role in both research and policy debates on education. However, the main international testing regimes, such as PISA, TIMSS, or PIRLS, include very few low-income countries. For instance, most countries in Southern and Eastern Africa have opted instead for a regional assessment known as SACMEQ. This paper exploits an overlap between the SACMEQ and TIMSS tests—in both country coverage, and questions asked—to assess the feasibility of constructing global learning metrics by equating regional and international scales. I compare three different equating methods and ﬁnd that learning levels in this sample of African countries are consistently (a) low in absolute terms, with average pupils scoring below the ﬁfth percentile for most developed economies; (b) signiﬁcantly lower than predicted by African per capita GDP levels; and (c) converging slowly, if at all, to the rest of the world during the 2000s. While these broad patterns are robust, average performance in individual countries is quite sensitive to the method chosen to link scores. Creating test scores which are truly internationally comparable would be a global public good, requiring more concerted effort at the design stage.