In this paper, an optimal tuning tool is presented for control structures based on multivariable proportional-integral-derivative (PID) control, using genetic algorithms as an alternative to traditional optimization algorithms. From an educational point of view, this tool provides students with the necessary means to consolidate their knowledge on these control structures, which are of particular relevance in control engineering. The graphical user interface designed for the tool allows for the following: the selection of the control structure, the desired decoupling, the type of PID, the analysis of the interaction effects through relative gain array (RGA), the planning of several optimal tuning processes, the comparison of different designs (through graphics or the numeric results obtained), and the management of data files saved during the planned optimal tunings process. The developed tool was made available to students for them to solve a practical problem and, subsequently, the impact of its use was evaluated. (Contains 5 tables and 14 figures.)