Social comparisons on traditional social networking sites (SNSs) such as Instagram can increase envy and reduce well-being. In this context, authenticity-driven SNSs such as BeReal intend to nudge their users towards sharing authentic and everyday content, thus reducing envy-inducing social comparisons occurring on traditional SNSs. However, it is unclear whether the content shared on authenticity-driven SNSs is indeed perceived as more authentic than on traditional SNSs, and how this affects SNS envy and well-being. Moreover, the relevance of perceived content authenticity next to self-esteem as an established envy antecedent remains unclear. Using two surveys, we found that BeReal content was perceived as more authentic than Instagram content. Furthermore, higher perceived content authenticity and self-esteem were associated with lower envy and increased affective well-being on both BeReal and Instagram, with self-esteem being a stronger predictor. This suggests that SNS design can reduce SNS envy, yet personal traits remain relevant predictors.