This study presents a heuristic evaluation and analysis methodology to enhance online platform usability. Recognizing usability’s critical role, especially in the information-rich online environment, the methodology employs expert evaluators using predefined heuristics for interface usability and information structure assessments. Twelve evaluators identified 71 usability issues on a patent-related matching service platform. Using Nielsen’s heuristics and affinity diagrams, these issues were categorized into 13 groups. A quantitative evaluation framework was developed with Quality Function Deployment (QFD) matrix, linking customer requirements to usability improvements. The card sorting methodology restructured the website’s menu and navigation system, resulting in a proposed sitemap redesign with a “Case Studies” menu and reorganized “Users” and “Experts” categories. The framework effectively identifies and prioritizes usability issues, providing a practical tool for small-scale enterprises. Future research should compare usability with competitors and develop decision-support systems to enhance user-centered design and website development.