PurposeBrands gradually became the core dimension and strategic asset of branding for organizations of all sizes, and today many companies adopt various forms of green marketing activities as part of their strategies. The objective of this study was to investigate and develop the psychometric properties of precision and validity of a scale for brand evaluation equity based on the environmental sustainability of the Brazilian Amazon.Design/methodologyThe scale was validated by adopting the standards described in the Standards for Educational and Psychological Testing APA. As samples for validation tests, eight companies were selected for among the ones who develop their business model in the Brazilian Amazon region. The data were applied to 262 potential consumers.Findings A scale with 22 items was constructed and validated, and after evaluation by the specialists, 22 items were obtained, divided into four dimensions: Brand quality perception — BQP (6 questions); Strategic Brand Positioning – SBP (10 questions); Willingness to purchase — WtB (3 questions) and Innovation in retail — INM (3 questions). Three items were modified because they presented the CVC at 0.8 and were accepted after the adjustments. The instrument items showed good internal consistency (0.877) regarding their domains. For DIF data, the scale invariably works for older and younger people for almost all items, except item INM 04.Research limitations/implicationsThis article fills the gap in the literature by developing a scale to assess consumer perception of brand equity and environmental sustainability. However, the findings are limited to the variation in the data collection. Considering the period of COVID-19 pandemic, most participants chose to fill in the scale online. Thus, the scale data are limited by the context in which the research was applied.Practical implicationsThe development and subsequent validation of the contextualized psychometric scale fills an important gap in the academic literature, providing a better understanding of the perception of potential consumers about the sustainable brand equity that generalist scales could not measure. Likewise, the scale provides essential information for brand entrepreneurs who aim to develop their products in a sustainable way, an important tool for managers to test and validate the extent to which new advertising materials demonstrate brand authenticity.Originality/ValueThe present study contributes to the directional and effective branding of brands related to environmental sustainability, mainly from tropical forests such as the Amazon rainforest. Furthermore, the findings suggest that the developed and validated cross-culturally instrument can be applied to potential consumers aged between 19 and 64 years of both sexes.