<span>The Time Dependent Ginzburg-Landau (TDGL) equation can be used to study the characteristics of superconductors in the evolution of time to reach equilibrium. This study uses the <em>ѰU</em> method to numerically calculate critical field values more easily. Previous research has been carried out on size variations, kappa variations, proximity effects and so on. In this study, a comparison between squares and rectangles with the same size of area for type II superconductor , then it is found that the critical field Hc<sub>3</sub> is the same value for each of the same area.</span>