The current preferred female lip ratio.

[BACKGROUND] Perception of beauty is influenced by the individual's demographic background and characteristics. However, objective measurements and ratios remain the foundation for aesthetic evaluations. This study aimed to elucidate if there exists a universally applicable ideal upper to lower lip ratio.

[METHODS] An interactive online survey was designed. Modifiable ranges of lip ratios were achieved via digital alteration, enabling participants to change the ratio of a single female model's lips. The questionnaire was translated into multiple languages and sent to more than 9000 plastic surgeons and the general public worldwide. Demographic data were collected and analysis of variance was used to investigate respective lip ratio preferences.

[RESULTS] A total of 1011 responses from 35 different countries (response rate of 14%) was gathered. The majority of survey takers (60%) chose the 1.0:1.0 lip ratio as most attractive. No differences were found in respect to lip ratio preference and the self-reported ethnicity. However, interesting preferences prevailed when analyzing the subgroups regarding lower lip size.

[CONCLUSION] Age, gender, country of residence, and profession significantly impact individual upper to lower lip ratio preferences. However, a 1.0:1.0 lip ratio can apparently be considered most pleasing in females.