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Most geopolymer research claims a substantial reduction in carbon dioxide emissions compared with ordinary portland cement concrete. However, geopolymer concretes are not all equally eco-friendly. The environmental benefits of geopolymer concrete cannot be taken for granted. Modeling emissions is necessary to assess the environmental impact of each geopolymer mix. Unfortunately, only studies concerned with carbon dioxide emissions care to provide sophisticated emissions modeling. Such modeling is practically nonexistent for other geopolymer studies; because function-oriented geopolymer research tends to assume the environmental eminence of their designed mixes. This research reviews the last 7 years of geopolymer concrete research to assess the sustainability of the mixes designed by researchers worldwide and to highlight any bad environmental practices in the mix design. The nominal CO2-e equivalent emissions for geopolymer concrete mixes varied from 56 to 661 kg-CO2/m3 for the surveyed mixes. SOx and NOx emissions reached 1,865 g-SOx/m3 and 1,161 g-NOx/m3 , respectively. Finally, this paper recommends a simple method for estimating a nominal carbon dioxide emissions value, which can be easily implemented in future geopolymer research. [ABSTRACT FROM AUTHOR]