Converted a complex Excel-based calculator into a fully interactive web application using React.js and Python. The application replicates the spreadsheet experience by allowing users to edit values, reorder rows with drag-and-drop, and view instant calculation results. It features dynamic forms, real-time calculations, sortable and filterable data tables, and a responsive interface optimized for desktop and mobile devices. The solution can be easily embedded into existing websites while maintaining high performance and accuracy.