Climate action is increasingly marked by the responsibilisation of individuals. In this context, carbon footprints have gained traction as a means of both quantifying individual responsibility for climate change and for motivating individual action through changes in behaviour. However, these mechanisms raise questions for climate justice in terms of how such moral and political responsibility is configured and distributed within the city. Drawing on a case study of Hong Kong, this paper explores the ways in which carbon footprinting configures responsibility for climate action by juxtaposing carbon footprints and the associated techniques of quantification alongside a discussion of the everyday practices of residents in a low‐income neighbourhood. It argues that carbon footprints offer important opportunities for measuring the impacts of carbon‐intensive activities and generating discussions about the allocation of responsibility for addressing climate change. However, it also demonstrates that individual carbon footprints ignore the uneven nature of carbon emissions in cities as well as obscuring important questions about the roles and responsibilities of other actors. In conclusion, the paper calls for an approach centred on common but differentiated responsibilities for carbon production and consumption to enable a more nuanced configuration of climate justice in the city.