Due to the concern that achieving human wellbeing through material development is “costing the Earth”, a mental model was developed to show the tradeoff between social foundations of development to be achieved and biospheric boundaries not to be crossed. Anthromes analysis, combined with the cultural imperative of maintenance of global sustainability through coordinated transformation of social metabolism and its environmental impact, makes nation states anthromic units of sustainability modelling. In the current century humans need to equitably meet their needs within the biophysical means of the planet. This is represented by boundaries along the outer rim of the doughnut coupled with the culturally desirable social foundations along the inner rim. For a single modelling tool to bring these concepts closer to potentially having a political and organizational impact, downscaling of planetary boundaries and social wellbeing foundations is performed through calculations of the impacts of nation states’ anthromic mosaics’ socioeconomic activities. To visualize the scale and the possible pathways for the transformation of national and global sociometabolic practices in the 21st century within equitably downscaled safe and just space (SJS) of the doughnut model, a “degrowth doughnut” includes the boundaries and thresholds in all of its three constituent segments along the ring: cultural, socioeconomic, and biophysical. This way it aims to avoid the conceptually paralyzing trade-off between biophysical boundaries and social thresholds alone, which has been found to currently offer no examples of securing social foundations without global environmental destruction. Understanding that excesses and shortfalls of current and foreseeable socio-metabolic practices exist in cultural, socioeconomic, and biophysical aspects of different national anthromes allows us to make comparisons between them. The aim of the model and its visual tool is to inform their populations about the direction and scale of the change strategies that they could adopt to contribute to the global effort of maintaining the planetary population within the safe and just operating space of the doughnut under known metabolic constraints of the 21st century.