With the international rise of data-based education governance, Germany has equally seen an increasing prevalence of data in school governance. This includes the datafication of school supervision (‘Schulaufsicht’) which supports and simultaneously controls schools. The study explores how school supervisors’ practices are (in-)formed by their datafied structurations (such as platforms, data overviews, etc.) and their professional self-perceptions. The article draws on qualitative interviews with ten school supervisors in four German states. The findings suggest that datafied structurations are widely used and influential (especially with regards to quality assurance meetings). At the same time, the supervisors continuously re-contextualize and qualify the datafied structuration. Furthermore, the interviewees highlight the importance of other knowledge sources and a trusting relationship between schools and school supervisors. In general, how datafied structurations influence supervisory practices depends highly on how supervisors perceive their profession.