This thesis aims to draw attention to the multi-modal transit system that is mainly applied in urban areas. In the context of the Paris Agreement, the transportation sector is identified as a major contributor to CO2 emissions in the United States. Meanwhile, there are ongoing observable unfair distribution of access to transit systems. The multi-modal transit system is then designed and expected to improve mobile equity for urban areas. A novel two-step methodology is designed that includes determining the Mobility Index (MI) for community-level accessibility and a city-wide Mobility Equity Metric (MEM). For instance, analysis is conducted based on the data from points of interest and socio-demographic factors to assess disparities across twelve major U.S. cities. Findings reveal significant variances in accessibility, with implications for policy aimed at enhancing equitable urban mobility and addressing the needs of disadvantaged groups. By the end, the research underscores the importance of integrating social considerations into sustainable transportation planning to achieve equitable outcomes.