Natural disasters pose significant threats not only to the environment and infrastructure but also to human lives. Therefore, effective disaster risk management must account for physical and social vulnerabilities. This research focuses on developing a comprehensive tool for assessing social vulnerability to enhance disaster risk management strategies. Social vulnerability is a complex concept that includes various dimensions, such as socio-economic and cultural factors. Recognising the multifaceted nature of vulnerability, this study aims to create a multidimensional index that equally represents each dimension of social vulnerability. By incorporating intersectionality theory, the research acknowledges that vulnerability is compounded and varies across different population groups. The proposed multidimensional index method introduces new calculation tools to balance the weights of all social dimensions in the composite index. Utilising socio-economic data from Indonesia, this study calculates the social vulnerability index and compares it with the existing Social Vulnerability Index (SoVI) to identify deviations and improvements. To validate the applicability of this alternative calculation, the study applies the new index to real disaster scenarios, specifically focusing on flood events in Indonesia. The research findings demonstrate that the multidimensional index effectively measures all aspects of social vulnerability in a proportional manner. The research also identified several significant policy implications, including the prioritization of policies, targeted policy development, and customized policies for disaster risk management.