Due to an increasing degree of automation in companies, a high availability of the equipment is required since its failure can result in high costs. To increase the availability of plants, various maintenance strategies can be pursued. The problem of different maintenance strategies lies in their cost causation. However, since maintenance only indirectly influences the operating result, key performance indicators (KPI) need to be developed that focus not only on the costs but also on the added value of maintenance. In this thesis, downtime costs are developed as one such metric that can serve as an effective means of representing the value added of a maintenance strategy. The aim of this thesis is to create a concept for automated downtime costing based on a pharmaceutical packaging. To achieve this goal, this work is divided into a theoretical and a practical part. In the theoretical part, the topics of maintenance, methods for calculating failure costs and data evaluation are covered. In the practical part of the thesis two packaging lines in a pharmaceutical company are analyzed. For this purpose, the company's internal SAP and OEE database system is accessed. The result is an Excel tool that can calculate the downtime costs per hour of two packaging lines based on the developed calculation model.