Vertical urban planning is increasingly adopted globally as a pivotal strategy for responding to urban growth, offering increased living and working space while reducing urban footprint. However, vertical densification presents potential environmental challenges such as reduced natural ventilation, compromised thermal comfort, and degraded air quality. These environmental outcomes are profoundly dependent on the complex interplay between built form and local climatic context. Prevailing design strategies often inadequately consider this critical dependency, transferring design approaches across different climatic contexts without adequate adaptation. To address this gap, this research proposes a simulation-based methodology to quantify climate-specific environmental habitability priorities for vertical urban design. Using Melbourne as a temperate case study and benchmarking against subtropical Hong Kong, the study employs urban modeling integrated with CFD simulation to quantify the weighting and relative importance of different habitability factors across climates. These insights will enable adaptive strategies for vertical urban development that balance density targets with environmental habitability requirements, providing practical guidelines for creating optimal vertical cities globally.