Conventional modeling and simulation of n-output DC-DC converters requires (n+1) × (n+1) matrix computations. This approach increases the modeling approach’s complexity and increases the design and simulation time required for the modeling process. A state separate modeling methodology is proposed where each state of the DC-DC converter is considered separately and combined with the help of a multiplexer. The proposed modeling approach is modular and thus improves the scalability to multiple outputs. The proposed methodology aids the designer in designing and modeling multi-output DC-DC converters faster, enabling fast prototyping. The proposed model outperforms the existing mathematical models in terms of computation time. The output voltage variation to duty cycles has a root mean square error in between 0.08 V and 0.22 V. IEEE