A larger ratio of Middle-Third to Lower-Third for Face-Height is considered a feminine feature, while a smaller ratio is a masculine one. A study suggested that the growth rates of different parts of the face vary as children develop into adults, with distinct patterns observed in boys and girls. Women’s faces are often associated with a larger middle area (including nose and maxilla) compared to the lower area (jawline), leading to more pronounced cheekbones, a smaller and shorter nose, and a rounder face. This creates a greater middle to lower face-height ratio, contributing to perceived femininity, as highlighted in Lakhiani & Somenek’s (2019) study. In contrast, men’s faces typically have a larger lower area, leading to a heavier jawline, taller chin, and squarer overall appearance. Consequently, the smaller middle to lower face-height ratio in men is seen as a more masculine feature.
According to Ferrario et al. (1998), as children grow into adults, different parts of their faces develop at different rates, and this happens differently for boys and girls. The face can be divided into three parts – the upper third (forehead), the middle third (including the nose and maxilla), and the lower third (including the mandible or jawline).
In girls, the upper and lower thirds grow quickly until around 11-12 years old, but after this age, the upper and lower thirds have roughly the same volume. However, for boys, the growth rate of the lower third (or the jaw area) picks up around 12-13 years old and continues until adulthood, making it larger than the forehead area.
The middle part of the face, which includes the nose and maxilla, grows at a rate similar to the overall face for both boys and girls. But here’s where it gets interesting: in girls, the ratio of the lower third to the middle third of the face remains relatively steady as they grow older, hovering around 80% in adult women. This means that the middle part of their face is proportionally larger compared to their jaw area. For boys, however, the lower third of their face (or the jaw area) grows more than the other two parts of their faces as they mature, causing the lower-to-middle third volume ratio to increase with age. By the time they’re adults, the jaw area takes up around 90% of the volume of the middle part of their face.
Thus, when we talk about the ratio of the middle third to the lower third of the face, a larger ratio means a larger middle part of the face compared to the jaw area, which is more common in women. Hence, a larger ratio of middle-third to lower-third for face height is seen as a feminine feature.
Additionally, in the context of sexual dimorphism, certain features are generally associated with femininity while others are linked to masculinity. Women’s faces are often characterized by a larger middle third relative to the lower third. This is, according to Lakhiani & Somenek (2019), due to features such as more prominent cheekbones, a smaller and shorter nose, and a more rounded face. This results in a greater middle-third to lower-third face-height ratio, contributing to the perceived femininity of the face.
In contrast, men’s faces usually have a larger lower third relative to the middle third. Male faces tend to have a heavier jawline, taller chin, and a squarer overall appearance, which results in a smaller middle-third to lower-third face-height ratio. This, in turn, contributes to a more masculine appearance.
Ferrario, V. F., Sforza, C., Poggio, C. E., & Schmitz, J. H. (1998). Facial volume changes during normal human growth and development. The Anatomical Record: An Official Publication of the American Association of Anatomists, 250(4), 480-487.
Lakhiani, C., & Somenek, M. T. (2019). Gender-related facial analysis. Facial Plastic Surgery Clinics, 27(2), 171-177. https://www.facialplastic.theclinics.com/article/S1064-7406(19)30006-9/fulltext