Restaurants are one of the main sources of wealth in the tourism sector and have significant potential in the fight against poverty reduction and the lack of development of local communities. However, in relation to the emission of greenhouse gases and the generation of waste, they are seen as two of the less sustainable sectors of the world. This study has the objective of providing a method to determine the level of sustainability in restaurants by means of modeling the OKR method and fuzzy logic. For this, 100 key results from the environmental, social, and economic dimensions were selected, using the fuzzy direct rating method to validate and weight the key results. The method is shown in advance, noting how and at what intensity the key results are inserted in the restaurant, indicating the strong and weak points of each restaurant in regard to sustainability. The results of this study contribute by providing a method that measures the level of sustainability in restaurants, identifies the current panorama and existing challenges, and allows for a complete mapping for the elaboration of strategies for improvements in organizational sustainability.