This study proposes and verifies the performance of an analysis tool for visualizing online interactions. A review of the most widely used methods for analyzing online interactions, including quantitative analysis, content analysis, and social network analysis methods, indicates these analysis methods have some limitations resulting from their one-dimensional analysis approach. To overcome such limitations, we developed the Multidimensional Interaction Analysis Tool (MIAT) by considering the advantages of well-known methods and incorporating the concept of the comparative interaction level. To verify the performance of the MIAT as a tool for multidimensional visualization of online interactions, results of the one-dimensional interaction analyses and those of the MIAT were compared. Findings suggest that the MIAT can provide a more in-depth interpretation of online interaction than any one-dimensional analysis method. In addition, the MIAT allows researchers to customize their analysis frameworks based on their own theoretical backgrounds. (Contains 7 figures and 4 tables.)