Indicators and Open Data for Smart Cities: A Comprehensive Study Across Brazilian Municipalities

Standardized urban indicators are essential for assessing smart and sustainable cities, yet their application in developing countries remains limited. This study addresses the critical gap regarding the availability of ISO 3712x standard indicators among local governments in Brazil—a nation marked by territorial and socioeconomic heterogeneity. Urban indicators based on open government data across all 5570 Brazilian municipalities were analyzed in this study using the ISO 37120, 37122, 37123, and 37125 standards. A synthetic smart and sustainable cities index was drawn up, supported by Factor Analysis and Principal Component Analysis (PCA). Considering the Local Indicator of Spatial Association (LISA), clustering patterns of municipal sustainability and smartness performance were identified: LISA analysis identified pronounced spatial clusters, with high-performance municipalities concentrated in the Southeast and South-Central regions, while low-performance clusters spread across the North and Northeast of Brazil. Despite the diversity of characteristics among Brazilian cities, 22 of the 302 ISO 3712x indicators (7.3%) could be collected with complete national data for all 5570 Brazilian municipalities; data for 59 indicators were available from open sources, though with gaps. Since the ISO 3712x standards offer a voluntary portfolio of indicators rather than a mandatory set, partial data coverage does not make the framework inapplicable; rather, they delimit the scope of the synthetic index presented here and highlight where open-data infrastructure must be strengthened. Municipal smartness and sustainability result from the multidimensional integration of technological innovation, human capital, social protection, and responsible environmental management. Despite the availability of ISO indicators, observations based on the authors’ institutional experience as members of ABNT/CEE-268—Brazilian mirror committee of ISO/TC 268—“Sustainable cities and communities”—reveal that local governments face challenges in systematically integrating them into strategic planning, presenting a significant opportunity for capacity building and evidence-based governance. In addition to the innovative aspect of this research—which involves using ISO-standardized indicators and collecting numerical data from official open data sources—this article presents a comprehensive index calculation for sustainable and smart cities based on these indicators, followed by the identification of its spatial clusters.