This working paper introduces the Crop Potential Productivity Index (CropPI), a global index that integrates Earth Observation Big Data with FAO’s Crop Requirements Database to assess the potential productivity of key staple crops (maize, wheat, and rice). The index combines climate, water availability, and soil parameters into a high-resolution (250m) spatial indicator and includes a penalization strategy for seasonal stressors. CropPI has been tested in 11 African countries and validated against Net Primary Productivity (NPP), DSSAT-simulated yields, and GAEZ data. The paper discusses its applicability for policy, planning, and climate adaptation, and offers recommendations for future improvements, including dynamic phenology, irrigation data integration, and AI-based validation.