The user interface design of an application is not limited to applications in the field of informatics, but also applies to various fields that utilize information technology. This also applies to educational evaluation. A good evaluation application is the result of a good user interface design. The aim of this study is to demonstrate the user interface design of the JOFF (Justification–Observation–Finalization–Functionalization) evaluation application which is derived from the DIVAYANA (Description–Input–Verification–Action–Yack–Analysis–Nominate–Actualization) evaluation model. The improved version used is Borg and Gall with a focus on three stages, together with: layout development, preliminary trying out, and revision of the initial checking out effects. The number of respondents involved in conducting the initial testing of the user interface design of the JOFF evaluation application was 44 people. Four experts and 40 IT vocational school teachers at several IT vocational schools in Bali. The statistical series device in this study turned into a questionnaire. Questionnaires are used to obtain quantitative data from subjects (respondents) who have completed initial trials. Analysis techniques of quantitative records accumulated from the preliminary trials were then used to analyze the usage of quantitative descriptive strategies. The effects of the study confirmed the great person interface layout of the JOFF evaluation software, which is a derivative of the DIVAYANA evaluation model, is classified as superb with a pleasant percent of 87.81%. The impact of this research on the field of educational evaluation is the existence of new knowledge about the importance of good user interface design.