Elysonia Alim and Shahabuddin Amerudin Department of Geoinformation, Faculty of Geoinformation and Real Estate, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia Email: elysoniaalim@gmail.com; shahabuddin@utm.my KEYWORDS: coordinate system, conversion, shapefile ABSTRACT: It is difficult to process GIS vector data when they are not aligned with one another. The need for different coordinate systems rose from the fact that some coordinate systems are better fitted to describe the geographical phenomenon occurring in a specific area. However, even commercial software had been proven to have questionable accuracy in coordinate system conversions. The purpose of this study is to develop a web application capable