Abstract Today, factories have to be adapted permanently in order to follow the developments towards fast changing customer demands and faster life cycles of products. Key aspects to cope with these developments are the reduction of the unit costs and the planning duration as well as the improvement of the planning quality. In order to overcome these challenges, digital tools can support all phases of factory and process planning. Most of them provide a wide range of functionalities, which require a large invest in software and high operation costs to use them efficiently. Often, small and medium enterprises (SME) cannot afford such invests and operation costs. Therefore, new digital factory planning tools tailored for SMEs supporting the production system planning are required. Main goal of the “WiES-Pro” project, funded by the Ministry of Finance & Economics Baden-Wurttemberg, was to develop an engineering environment for production system planning suitable for SMEs. The “WiES-Pro” approach connects small specific software tools for production system planning in an integrated platform, capable to share information and knowledge easily. The challenges in the development are to cope with both the heterogeneous data from different sources like machine master data, work plans or product data and the applicability to SMEs. This paper presents the results of the project, consisting of the approach and its implementation. Also the architecture of the browser-based platform and the developed digital factory planning tools for priority graph optimization, assembly process time planning, similarity-based product search and material flow simulation are presented shortly.