Background <p>Information literacy depends on diverse skills in processing information, including understanding graphs properly. Especially for those advising and informing people with less information, health and graph literacy, it is important to achieve high competence in these areas themselves. Graph literacy, therefore, is a form of semiotic activity that is a crucial component of overall literacy for (future) physicians. We analyzed the graph literacy of undergraduate medical students to gain knowledge about their skills and potential areas for improvement.</p> Methods <p>An observational cross-sectional survey study was performed with undergraduate medical students in their academic years 1 to 5 using the “Graph Literacy Scale.” It measures the participant’s ability to read and interpret graphically provided information with 13 questions in three dimensions regarding visual data: “reading the data,” “reading between the data,” and “reading beyond the data.” Participants can score between 0 and 13 points.</p> Results <p>We obtained 449 complete questionnaires. Undergraduate medical students showed above-average test results compared to the German standard population, with an average score of 11.42 (<i>SD</i> = 1.42) vs. 9.4 points (<i>SD</i> = 2.6) points (<i>p</i> &lt;.001). Although students generally scored high, one question measuring the ability to visually “read beyond the data” yielded significantly lower scores and showed variability regarding the participants’ performance compared to other questions of this category.</p> Conclusions <p>While abilities in visually “reading the data” and “reading between the data” are high in our cohorts, their ability to visually “read beyond the data” is inconsistent. This requires attention in the training of medical students, as weaknesses in this area could lead to susceptibility to misleading data. Enhancing graph literacy in medical students is crucial for effective physician-patient communication.</p>