The ecological footprint estimates the impact of individuals in nature as they maintain their lifestyle. It can be used as an indicator of environmental sustainability applied to individual lifestyles, regions, and nations. This study aimed to assess the ecological footprint and the awareness of sustainability of consumers based mostly on their choice of consumption of cotton clothing. The estimation was based on the answers to an online questionnaire containing questions related to the subject lifestyle. The ecological footprint was calculated, and the results were analyzed using data mining, considering the cross-validation using 10% of the samples to obtain a decision. The results show that the better the index of the ecological footprint, the greater the awareness of the issue by the consumer.