Abstract: QoL studies conceptualise urban well-being as a multidimensional process that is influenced by personal and environmental factors. A much less explored field in QoL has to do with the notion of capabilities and functionings as measurements to evaluate the level of quality of life that people experience in cities. By investigating the young adults category, this article develops a measurement of QoL based on the normative framework of the Capability Approach (CA) to capture urban domains that affect quality of life in Bogota. This study introduces a quantitative methodology to use secondary aggregated data to build a QoL measurement based on capabilities. A nonlinear categorical principal component analysis was used to explore the underlying factor structure of a calibration sample (n=6,998). Confirmatory Factor Analysis was conducted to validate identified factors, revealing a good fit (SRMR=0.033, CFI=0.910). The result is a Young Adult Capability Index (YACI) that empirically explores the use of capability achievements as a space for evaluating urban QoL in young adults. A multiple linear regression was calculated to predict YACI based on additional variables which are sensitive to inequality for young adults. Results show that capability scores are lower once young adults enter adulthood. Women arrive with better capabilities from childhood and adolescence than men, but rapidly undergo a marked process of decapitalisation of capabilities during their transition to adulthood, suggesting the need for more attention in the elaboration of public policies for this type of population.