E-Commerce has become an integral part of everyday life, giving customers easy access to a variety of products. Macksons Store, as an E-Commerce site that focuses on tools and building materials, faces challenges in improving the user experience to make it more efficient and satisfying. This research analyzes and develops the user interface (UI) and user experience (UX) of the Makckson Store by applying the User�Centered Design (UCD) method. The UCD method is used to understand user needs and preferences. The first step involves market and user analysis to understand the user context and business requirements. Next, datacollection was carried out through interviews, surveys, and observations. The results provide insight into user preferences, shopping barriers, and user experience expectations. Based on this analysis, the design process begins by designing wireframes and prototypes to get initial feedback from users. UCD enables initial user feedback-based design iteration to reach an optimal solution. Aspects such as navigation, product arrangement, ordering formulas, and
payments are the main focus of UI/UX development. It is hoped that the results of this research will increase user satisfaction, increase sales conversions, and strengthen
Macksons Store's position in the E-Commerce market for tools and building materials.
Keywords: E-Commerce, User Centered Design, User Interface