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 almost no low-income countries. Instead, many developing countries opt for regional assessments sponsored by the United Nations. This paper exploits an overlap between the regional test for Southern and Eastern Africa, SACMEQ, and the TIMSS test – in both country coverage, and questions asked – to assesses the feasibility of constructing global learning metrics by equating regional and international scales. I find considerable variance when comparing three commonly-used equating methods, suggesting precise country rankings are unreliable. Across all methodologies, however, learning levels in this sample of African countries are consistently (a) low in absolute terms, by roughly one-and-a-half standard deviations or more compared to OECD pupils of a similar age; (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. The robustness of these simple facts suggests even crude linking methods may suffice for many international policy questions, such as tracking the UN’s development goals.