A cost-benefit assessment can be a valuable tool in dairy management to assess an animal’s lifetime contribution to herd profitability and make timely decisions regarding cow replacement. We developed a user-friendly interactive decision-making support tool to visualize the impact of costs and revenues on herd and cow level. The interactive tool was built with the Shiny add-on package in R. The dashboard consists of side-by-side panels with a built-in drop-down list for costs (feed costs, costs of breeding services, costs of health events, additional costs due to health events and extra breeding services) and revenues (milk value, margin over feed costs, margin over all costs) cumulated on lifetime basis. Herd-level data allow users to compare herd performance to that of the rest of the population. Integrated benchmarking tools facilitate the comparison with specific cohorts, such as region, management system, and calving year. In addition, cow-level data allow monitoring individual cow performance and contribution to herd profitability. A comparison across lactations between the top and bottom 25% herds in terms of cumulative milk yield indicated a 4.5-fold larger cumulative milk value. Nonetheless, we observed 5.4-fold greater cumulative disease costs and 4.2-fold greater cumulative additional costs due to health events and extra breeding services. A lifetime cost-benefit assessment has the potential to inform producers on making informed culling decisions by considering cumulative costs and revenues. Visualizing the magnitude of the impact of cumulative costs, in particular that of health and reproduction costs, on lifetime profitability should stimulate dairy producers to consider cumulative events in their decision-making process in keeping the most profitable cows in their herd, and to keep detailed on-farm records affecting lifetime profit. Our dashboard tool adds to the dairy extension deliverables through a user-friendly interface that allows producers, veterinarians, and advisory services nationwide to make timely decisions to improve herd profitability.