A financial planner and portfolio simulation system projects the simulated cumulative risks and rewards of one or more mixed portfolios in relation to the expected risk and reward of a minimum-risk or relatively risk-free baseline portfolio. As a user enters portfolio input parameters, the system immediately computes, displays, and graphs an inflation-adjusted retirement budget that a baseline portfolio fully invested in minimum-risk assets would be able to sustain. The system also generates—through simulation—a probability distribution of average retirement budgets that the mixed portfolio(s) would be projected to sustain, and graphs various percentile-ranked samples from that distribution on the same computer-generated plot that displays the sustainable retirement budget supported by a baseline (minimum risk) portfolio. The statistical and graphical comparisons of the mixed portfolio(s) to the baseline portfolio assist investors in choosing mixed portfolios best suited to their retirement goals and risk tolerance.