Inventory management at CV. Dena Sukses Mandiri previously relied on separate spreadsheets, creating risks of stock discrepancies, delayed procurement, and difficulty distinguishing READY and INDENT items. This study develops a web-based Warehouse Management System using the Reorder Point (ROP) method to determine replenishment timing from average usage, supplier lead time, and safety stock. The system was developed with the Waterfall model using PHP, MySQL, Bootstrap, and XAMPP. Its implementation covers master data, incoming and outgoing transactions with approval, stocktaking, real-time stock monitoring, reorder alerts, automatic purchase requests, reports, and audit logs. Black Box testing of 24 scenarios found all functions valid. A System Usability Scale evaluation involving 11 respondents produced an average score of 80.45, corresponding to Grade A, Excellent and Acceptable categories, and an NPS classification of Promoter. These results indicate that the system satisfies its functional requirements and is acceptable to users for supporting data-driven inventory control.

Keywords— Warehouse Management System, Reorder Point, Inventory, System Usability Scale, Web.