The delivery of health, food, and shelter to the 68.5 million people displaced worldwide represents a significant challenge. Camps can house hundreds of thousands of people, and the provision of shelter on such a scale uses considerable amounts of energy and construction materials. Although there have been several attempts to calculate the embodied energy of small numbers of shelters, summary statistics for the embodied energy (EE) and embodied carbon (EC) in general remain unknown. This makes it impossible for those designing shelters to know where their solution sits relative to the median. The primary aim of this article is to resolve this gap by using data collected from eighty-one shelter designs in thirty-four countries to complete the first large scale and global estimate of the EE and EC of shelters. Second, it aims to introduce a web-based and open-access tool, developed to help any stakeholder or interested party obtain an idea of the EE and EC of their design. The median EE was found to be 920 MJ per m2 of footprint with a 95 percent confidence interval (CI) of 599 to 1200 MJ/m2. The median EC was 90 kgCO2e/m2; 95 percent CI [39.2, 99.6]. Importantly, when these figures were further normalised per annum of service life and statistically analysed, more robust shelters did not generally have a greater environmental footprint per annum. Just three material categories—metal, clay bricks/tiles, and concrete—were found to dominate EE and EC.