Consistency, as one of the most important features of usability, has been using as an important indicator of accessing usability. A number of studies recently have focused on how to create consistency in a single application, but few of them have noted how to create and evaluate the consistency across products in a same company. In this paper, we addressed the problem by using two methods, in-complete matching task and the methods of paired comparison, to analyze the distinction among the competitive products and evaluate the consistency of the current products. The study finds that these two methods can relative rapidly identify the performances of consistency between different products and be able to find out some design elements impacting the consistency. However, as the object of the study in this experiment is only involved in the login interface, the applicability of the method needs further studies.