Budget pressures necessitate a thorough examination of DevOps platform expenses beyond just subscription fees. Understanding the total cost of ownership (TCO) is crucial for defending platform spend and comparing financial options. A well-designed TCO model brings transparency, reveals cost drivers, and identifies savings opportunities. The true cost of a DevOps platform encompasses subscription access, CI/CD compute, AI usage, infrastructure, tools, and employee time. Different platforms package capabilities uniquely, making direct price comparisons misleading without considering specific organizational needs. A robust TCO model necessitates consistent scope and timeframes, separating recurring from one-time costs and internal from external spend. Key cost categories include platform access, CI/CD and AI consumption, runner infrastructure, security, additional tools, support, internal operations, and migration. Independent modeling of cost drivers like pipeline frequency and AI adoption is essential due to their varied impact. Runner strategy significantly influences CI/CD compute costs, with vendor-hosted and self-managed options presenting different tradeoffs. Tool sprawl, the gradual addition of various single-purpose tools, incurs hidden costs through integration maintenance, administration, and lost developer time. Utilizing a TCO worksheet can help estimate annual costs by itemizing platform licenses, compute, AI, tools, labor, and migration expenses. Right-sizing licenses, eliminating unnecessary CI/CD work, building flexibility into AI spend, matching runner capacity to demand, and consolidating tools where beneficial are key strategies for reducing overall platform TCO.