Since Higgins presented regulatory fit theory in 2000, over 200 studies have demonstrated that regulatory fit processes moderate both information processing and outcome responses substantially. However, scholars characterize regulatory fit diversely and manipulate the definition. Researchers have highlighted this issue and recommended further investigations to clarify regulatory fit heterogeneity, which is derived from two sources: conceptual viewpoints of regulatory fit and methods for regulatory fit induction (Aaker, 2006; Avnet, 2006; Cesario, 2008; Pham, 2009). This study decomposes manipulation heterogeneity for researching regulatory fit from the experimental methodology viewpoint. Rather than providing a summary of existing methods, this study proposes a critical moderator embedded in these techniques, which objectifies the regulatory fit concept using a calculable index. The proposed index can be used to predict the strength of the regulatory fit effect, and explain manipulation heterogeneity when researching regulatory fit.