OBJECTIVES: To inform decision makers who seek extension of Universal Mass Vaccination (UMV) about the most optimal allocation of funds across multiple preventative interventions or vaccines. To account for decision makers preferences using MCDA. METHODS: A multi cohort markov model was developed to assess clinical and economic consequences of vaccine preventable diseases in Japan. Disease incidence rates, direct medical costs and QoL data were obtained from local sources. Payer perspective only was considered. Optimization module utilizing linear programming was developed to maximize outcome of interest which serve as an objective function subject to budget and intervention coverage constraints. A working version of the model can be found at http://www.digitalho.com/models/a/portfolio/index.html. The model was initially developed in Excel and then automatically transformed into a JavaScript application to allow for an online access. One way sensitivity analyses was conducted to parametric unceranity.  RESULTS: Model results indicate that the optimal mix of interventions depends primarily on the objective function. Various single objective functions or a combination of multiple weighted objectives lead to different mix of interventions. When prevention of death is as an objective function then pneumococcal and rotavirus vaccines are chosen.  CONCLUSIONS: The proposed web based model is a complementary addition to the conventional cost-effectiveness assessment for preventative interventions. This model helps to understand sequence of introduction of prevantative interventions and expected health and economic outcomes over time. The use of MCDA framework helps users to define specfic health objectives to be used in optimisation module. The web based modeling solution provides a widespread access to an easy to use tool that can by used by authorities, academia and non-modeling professionals.