This chapter explores the multidimensional concept of data justice within humanitarian contexts, focusing on how quantitative data practices intersect with social injustices. Data justice refers to fairness in the way people are made visible, represented, and treated as a result of the ways in which data are made and used. The construct encompasses several interlinked dimensions, each offering a distinct lens on the intersection of data and social justice. Procedural data justice looks at fairness in how data is made, whereas instrumental data justice looks at fairness in how data is used. Rights-based data justice considers data rights and responsibilities, whereas structural data justice highlights the link between data and social structures. Finally, distributive data justice looks at fairness in the outcomes of a data project. The chapter argues that, without attention to these aspects, humanitarian data projects risk reproducing social injustices in disaster settings.