Background Novel strategies to complement current methods of education delivery by healthcare providers in clinic encounters or in pulmonary rehabilitation are needed to promote COPD self-management. Methods We developed a COPD web-based platform that delivers education as part of a physical activity intervention. We examined COPD knowledge in persons with COPD who used a web-mediated, pedometer-based physical activity intervention. Knowledge was assessed with the Bristol COPD Knowledge Questionnaire (BCKQ) at baseline, 3, 6, 9, and 12 months. Scores range from 0 to 100, with higher scores indicating greater knowledge. Repeated measures ANOVA (PROC MIXED, SAS 9.4) examined trends across the 12 months and identified changes from baseline at 3, 6, 9, and 12 months. Results We enrolled 72 participants with COPD, 93% males with mean ± sd age of 69 ± 7 years and FEV1% predicted of 60 ± 23%. There was a significant increase from baseline to 9 months (p = 0.012), although this increase did not persist at 12 months. Among the 13 topics, participants scored the highest at baseline on smoking knowledge (65.3 ± 17.4) and the lowest on inhaled steroids (9.7 ± 15.4). Across the 12 months, there were significant increases in knowledge about inhaled bronchodilators (p = 0.011) and inhaled steroids (p = 0.035). At 12 months, there were significant improvements in knowledge about exercise (p = 0.004), vaccination (p = 0.027), inhaled bronchodilators (p = 0.002), and inhaled steroids (p = 0.002). Conclusion An internet-mediated intervention may provide another option for COPD education delivery and support for disease self-management.