The Internet has become important for the delivery of behavior change interventions. This observational study examines how many people visited, registered and revisited a web-based computer-tailored intervention promoting heart-healthy behaviors when it is implemented for use by the general public. Among registered visitors, the association between visitors' characteristics and initiating, completing and revisiting the website and/or its behavior-specific modules was analyzed. Server statistics showed that 285 146 visitors from unique IP addresses landed on the home page in a 36-month period; of these, >50% left the intervention website within 30 s. In total, 81 574 (28.6%) visitors completed the registration procedure and gained access to the intervention; 99% of registered visitors initiated one module, 91% completed at least one module and 6% revisited the intervention. The majority of the registered visitors were women, medium to highly educated, with a body mass index (BMI) <25. Women, visitors aged 40-50 years, visitors with a medium educational level and visitors with a BMI <25 were more likely to initiate and finish the modules. It is concluded that a heart-healthy computer-tailored Internet program can reach substantial numbers of people, but additional research is needed to develop promotional strategies that reach the high-risk population, i.e. men, older and lower educated persons.