This article investigates the effectiveness of a newly developed online tool for assessing and improving the design and accessibility of Learning Management System (LMS) sites in Higher Education. The study employs a mixed-methods approach, incorporating both quantitative and qualitative data. Results from 25 subject coordinators and 3 peer reviewers reveal the strengths and weaknesses in LMS site design at a particular institution. It identifies recommendations for enhancements such as clearer signposting of educational materials, improved organisation of reading lists, and increased opportunities for collaboration. In addition, the research identifies key areas for improvement in institutional LMS site design, including consistency, organisation, and ease of navigation. These findings underscore the importance of engaging prior knowledge, fostering active learning, and ensuring clear communication of student expectations. The tool is shown to be a valuable resource for educators to assess and enhance their online teaching environments. The study's findings contribute to the ongoing discourse on optimising blended learning experiences, emphasising the need for ongoing improvement in LMS site design and accessibility.