The direct analysis to determine the transverse distribution of moments in stiffened bridge decks using the differential equation approach becomes laborious, especially in the preliminary design process where several trials are often required to determine the relative dimensions of slab and stiffeners for achieving optimum structural efficiency of the deck. The majority of design charts and tables available to the engineer during the preliminary design process assume absolute dimensions of slab, stiffeners, diaphragms, and their spacing, and thus are more suitable for detail design. This study deals with the development of design charts that express governing parameters in dimensionless form, and with the rapid evaluation of rigidity parameters and critical moments. Such design charts and tables are ideal for carrying out several trial sections to find the most economical structural system during the preliminary design process. The theoretical work is supplemented by a limited experimental programme and good agreements are found.