Abstract One of the strategies for assessing the relationship between the built environment and active behaviors is walkability, defined as the extent to which the built environment supports and encourages walking. Given this scenario, data aggregation is critical, however, there are still methodological challenges and a latent lack of experimental evidence on appropriate aggregation units for walkability in Brazil. Thus, the objective of the present work is to analyze spatial data aggregation units for the objective measurement of walkability and its individual variables in the context of a Brazilian city. From the systematization a walkability index, in different data aggregation units, e.g.: census tract and network buffers with radii of 200, 400 and 600 meters, data variability, and dispersion analysis were conducted. It was inferred from statistical results that buffers of 400 and 600 meters, with dimensions closer to average walkable distances, were more efficient. This study methodologically contributed to the advancement of contemporary approaches to understanding walkability through quantitative analysis.