The administration of examination seating in higher educational institutions continues to rely heavily on manual processes that are labour-intensive, error-prone, and ineffective at preventing malpractice. This paper presents the design, implementation, and evaluation of the Smart Exam Hall Seating Arrangement System (SESSAS), a zero-dependency, single-file web application that fully automates examination seat allocation while enforcing strict anti-malpractice constraints. The system accepts bulk student data through a CSV upload interface and applies a two-phase allocation algorithm: a Fisher-Yates randomisation pass followed by a department-interleaving round-robin distribution. A bench-enforcement mechanism further guarantees that no two students sharing the same department and subject are assigned to the same bench, directly eliminating adjacency-based malpractice opportunities. Students with special accessibility requirements are automatically placed in front-row positions prior to general allocation. The application is implemented entirely in HTML5, CSS3, and JavaScript, relying on PapaParse for CSV processing, SheetJS for multi-sheet Excel export, and jsPDF for landscape PDF report generation—all delivered within a single distributable HTML file requiring no server, database, or installation. Experimental evaluation on datasets of up to five hundred students across ten examination halls demonstrated complete seating plan generation in under three seconds, zero same-department bench violations, and a 100% reduction in manual administrative effort compared to conventional spreadsheet-based methods. The system further provides a real-time colour-coded seating grid, live attendance marking, absentee reporting, and an integrated statistics dashboard. These results confirm that SESSAS offers an efficient, portable, and institutionally deployable solution for modern examination management.