DESENVOLVIMENTO DE UMA PLATAFORMA WEB CENTRALIZADA PARA GESTÃO FINANCEIRA: UMA ALTERNATIVA INCLUSIVA E ESTRUTURADA ÀS PLANILHAS ELETRÔNICAS

The high number of defaulters in Brazil, which reached 81.3 million in January 2026, highlights the need for personal financial management tools more reliable than electronic spreadsheets, which are prone to calculation errors and offer limited data validation. This study aimed to develop a centralized web platform for personal financial management, with automated data validation, arithmetic precision, and accessibility features, as an alternative to spreadsheets. This is applied research, descriptive and explanatory in nature, with a qualitative approach. The platform was built with a Java and Spring Boot back-end, a Microsoft SQL Server database, and an Angular interface, and was validated through manual tests of API requests using the Postman tool and through a qualitative comparison with the spreadsheet-based method. The tests confirmed the expected responses for valid entries, invalid data, and unauthenticated access, and the BigDecimal type produced an exact balance of R$ 0.20 in a calculation in which the double type would yield 0.19999999999999998. The results indicate that the platform combines arithmetic precision, information security, and accessibility features in a single environment, constituting a structured alternative to spreadsheets, although the evaluation was limited to the author's observation.