Sundhed.dk is Denmark’s national eHealth platform allowing citizens to access their personal health data. Based on 16 qualitative interviews with patients, our aim in this article is to examine how patients engage with their health data. First, we illustrate how patients struggle in different ways to make sense of numerical measurements and written notes. Second, we examine the platform as a communicative space and suggest that a new “medical-domestic” space arises in which medical data is interpreted and negotiated at home. Third, we investigate how health data affects patients’ experiences of being involved as equal partners and how access to data potentially enhances patient empowerment, but also how expectations are sometimes unfulfilled. In conclusion, we argue for a broader public dialogue in order to make sure that the data provided actually creates an optimal starting point and does not foster insecurity or self-doubt on the patient’s side.