A computer model is developed, capable of predicting the flow distribution along the height of a fuel-cell stack. The model distinguishes a number of hydraulic resistances that are linked in series and parallel, thus forming a network to simulate the gas flow and pressure distribution in a stack. The hydraulic resistances are found from analytical solutions or from tabulated data inferred from measurements. The electrochemistry of the stack is simulated by adding or subtracting gas in the active cell area. The model is tested on an assumed separator-plate geometry and stacking height.