Background: Many informal caregivers of older adults have limited time because of the number of responsibilities that their caregiving role entails. This population often experiences high levels of burden due to the stressful nature of their work and are vulnerable to developing negative psychological health outcomes. Easily accessible and flexible knowledge interventions are needed to alleviate the burden and stress experienced by this group. Objective: This study aims to evaluate the acceptability of the web-based delivery of the Caregiving Essentials course for informal caregivers of older adults. Both the strengths and limitations of using a web-based platform to provide information and resources were explored to see whether the method of delivery enhanced or hindered the overall course experience for participants. Methods: A mixed methodology of web-based pre- (n=111) and postcourse surveys (n=39) and telephone interviews (n=26) was used to collect both qualitative and quantitative data from participants. Individual interviews were also conducted with key stakeholders (n=6), and a focus group was conducted with nursing students (n=5) who were involved in the project. Results: The web-based delivery of the course provided participants with greater accessibility to the course because it allowed them to work independently through the modules at their own pace wherever and whenever. The discussion boards were also identified as a major strength because of the opportunity for social interaction and the sense of community that many felt through sharing their experiences. Some barriers to participation included age-related factors, issues with navigating aspects of the course, and concerns about privacy and anonymity. Some key suggestions included more engaging methods of web-based communication and the reorganization of the module content to reduce the amount of text and streamline information. Conclusions: The web-based delivery of Caregiving Essentials appeared to enhance the overall course experience by increasing accessibility and allowing participants to interact with the learning materials and other caregivers. The findings from this evaluation can be used to create and improve the web-based delivery of both the current and emerging interventions for caregivers.