One of the developments in the field of educational evaluation utilized as an evaluation tool to identify the key elements that drive the success of blended learning is the TOPSIS-TTA-based Discrepancy evaluation application. This evaluation application combines the TTA (Tat Twam Asi) concept, the TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) method, and the Discrepancy evaluation model concept. The purpose of this study is to demonstrate the implementation outcomes of the TOPSIS-TTA-based Discrepancy evaluation application at IT vocational schools in Bali, as well as the results of usage trials, final product revisions, and its dissemination. The research method used focused on the usage trial stage, final product revisions stage, dissemination stage, and implementation stage. The usage trials comprised 39 respondents, while the application test involved 150 participants. For the final product revisions, three research team members were engaged, along with 150 respondents during the dissemination activity. The assessment instruments employed during the trial usage and application testing were questionnaires. Bali’s IT vocational schools served as the study’s location. The study’s data analysis method was descriptive quantitative by converting the results of the application effectiveness percentage which has been compared with the standard effectiveness scale of eleven. The findings of this investigation suggest the effectiveness level of evaluation application including the advanced category, so that in general the evaluation application is ready to be implemented on a wide scale in the field. The significance of this study in the field of educational evaluation lies in its ability to simplify the process for evaluators in choosing high quality evaluation tools, relying on dependable trials of application implementation and usage.