Anode melting of blister copper based partial removal of impurities with a having high affinity for oxygen. The centralized process of refining one plant is complicated by the different and variable chemical compositions of the charge of blister copper supplied by different factories - producers. Therefore, is constantly changing, the weighted average composition of the liquid metal depending on each load, therefore requiring a different amount of oxygen for oxidation and slagging. The aim of this work is to develop a methodology for calculating a theoretically required oxygen concentration in the melt of the mass, (t): Cu2O as the target function of the mass of the impurity of blister copper. Using the method of regression analysis, we developed a mathematical model approximating function O2 = f(Cu2O), which can be used to quickly calculate the concentration of oxygen supplied to the melt oxidation stage of fire refining. The results revealed of the regularities built a graph dependencies of the concentration of oxygen in the melt by mass of copper oxide (1). Mathematical description is made on the basis of the average composition of the mixture from four factories - producers. The algorithm model is built based on passive experiment, with the selected assumptions and limitations. It is established that the described algorithm with the use of MLS on the platform applied Microsoft Excel and the stoichiometric oxidation reactions of impurities shows a linear dependence of the concentration of oxygen supplied to the melt by mass of copper oxide (1), indicating the adequacy of the obtained model.