This article introduces the notion of 'humanitarian ignorance' to address the growing concern of non-knowledge as datafication becomes a central instrument and ambition for the humanitarian sector. With the turn to digital humanitarianism, contemporary humanitarian action increasingly relies on technology-driven quantification to expand the ability to collect, analyse, and present information. Utilizing datafication processes, humanitarian organizations seek to assess 'risk' and mitigate 'uncertainty' more efficiently. Though central to organizations' knowledge management and decision-making in low-information circumstances, we argue that the conceptual notions of 'risk' and 'uncertainty' are inadequate to capture the full spectrum of non-knowledge in times of digital humanitarianism. Here then, we introduce 'humanitarian ignorance' to challenge the assumption that datafication allows humanitarian organizations to make fully informed, delimited, thus 'better' decisions about the present and future. We ultimately accentuate the paradox that while datafication is thought to reduce risk and uncertainty in humanitarian affairs by suggesting higher levels of control, insight, and certainty, these efforts in fact open new expanses of ignorance and unknowns in humanitarian affairs.