This study aims to develop the analysis tool that assesses the sunlight at any given point of a window or solar collector array shaded by surrounding obstacles. The development of this software, named SunChart, focused to the user-friendliness and the reliability. This SunChart can calculate the solar radiation as well as shading on the certain face. The calculation results by SunChart show by both numerically and graphically and are in a good agreement with ones obtained from "Sunrise Sunset" developed at Korea Astronomy Observatory and from TRNSYS.