The rapid advancement of alternative energy and energy-saving technologies in China underscores the importance of conducting a comprehensive analysis of the total cost of ownership (TCO) for commercial vehicles such as buses and trucks. To address the challenges of quantifying time-sensitive and implicit costs, this study has developed an extensive database and a web-based modeling tool to evaluate the TCO of these vehicles for the period 2020–2040. The tool allows for user-customized inputs and generates TCO estimates across multiple technology evolution scenarios, encompassing nearly 200 vehicle types categorized by class, intended use, and powertrain technology, within diverse technology development pathways. The model integrates critical cost factors, including vehicle purchase costs, financing costs, energy expenditures, and inconvenience costs, providing a detailed assessment of long-term ownership costs. Key findings indicate that under the reference scenario, battery electric buses are projected to achieve significant cost reductions of 30–40% by 2040. Similarly, fuel cell electric trucks are expected to reduce costs by 35–45%, potentially exceeding the cost reductions projected for battery electric trucks. Conversely, conventional vehicles such as those powered by compressed natural gas/liquefied petroleum gas (CNG/LPG) or compression ignition (CI) technologies are unlikely to realize substantial TCO savings over the same period. Among vehicle classes, intracity transit buses (M3 class) are anticipated to experience the most notable TCO reductions, potentially exceeding 50%, while mini buses consistently maintain the lowest TCO. Under a more pessimistic scenario, cost reductions are either limited or marginally increased for certain vehicle types, such as CI buses. This web-based platform is designed to offer valuable insights and guidance for fleet operators, policymakers, and manufacturers, supporting informed decision-making and strategic planning in the development and adoption of sustainable commercial vehicle technologies in China.