Several methods exist to schedule specific workpieces in a manufacturing system. Large multinational companies usually apply worldwide automated scheduling systems to provide optimal manufacturing parameters and fulfil the requirements of the lean method. In contrast, an average small-medium sized enterprise (SME) has limited financial and technical resources to complete this task. This paper proposes an ultimately simplified fuzzy inference system, the Compact Mamdani Fuzzy Inference System (CMFIS), to help the scheduling tasks in SMEs. The CMFIS does not require special fuzzy logic knowledge and communicates with the user via Microsoft Excel worksheets. The paper introduces the CMFIS itself and its job shop application as well.