Introduction <p>The COVID-19 pandemic disrupted medical education globally. This study evaluates the effectiveness of the International Emergency Medicine Education Project’s online COVID-19 Clinical Readiness Course in enhancing participants’ knowledge and perceived confidence in managing COVID-19.</p> Methods <p>This is a prospective, mixed-methods study. Quantitative data were collected through pre- and post-course assessments and surveys, while qualitative feedback was gathered via open-ended responses at the end of the course. Non-parametric tests were used for statistical comparisons, and thematic analysis of qualitative data was performed using customized large language model tools with human review and triangulation.</p> Results <p>A total of 703 participants from 72 countries enrolled, 644 (91.6%) completed the knowledge assessments, and 510 (72.5%) completed the exit surveys. The majority (77.2%) were medical trainees, and 51.4% were from low- and lower-middle-income countries. The median score increased from 60 to 92 (<i>p</i> &lt; 0.001) post-course. Perceived confidence in managing key clinical scenarios, including hypoxia, early symptoms, airway problems, sepsis, and cardiac arrest, also increased significantly (<i>p</i> &lt; 0.001). Participants reported that the course met their expectations, with a median (IQR) score of 9 (8–10). Qualitative feedback revealed high satisfaction and highlighted areas for improvement.</p> Conclusion <p>The online Clinical Readiness Course significantly improved knowledge and perceived confidence in COVID-19 management among medical trainees worldwide. Scalable online education may help address training gaps during public health emergencies and support global medical education.</p>