Silos are essential structures for maintaining the quality of agricultural products used by the industrial, agricultural and mineral sectors, such as grains, seeds and other agricultural inputs. The determination of the physical and mechanical characteristics of the goods to be stored is necessary for the correct silo design and dimensioning, because these characteristics affect the type of flow, as well as the intensity and distribution of stresses in the structure. Therefore, when planning or changing a loading and unloading system, product characterization should be one of the first steps.This material is a guide for sizing a grain storage unit, with all the necessary calculations.