For centuries people have been trying to figure out what it is that makes someone more beautiful than others. There is no simple answer to this question. We often hear the phrase, “beauty is in the eye of the beholder”. However, is it possible that there are certain features that are recognized as beautiful universally around the world? Kalology is the study of facial beauty and the way in which our beauty affects our lifestyle and role in society. For beginners, I recommend you to read the following post to understand the basics of facial beauty.
In this study, we are going to explore what makes one face more beautiful than others and how artificial intelligence can assist us in processing our features.
Statistical Analysis, AI, and beauty
The ever-evolving technology and knowledge derived from a range of studies have paved the way for various statistical analysis and artificial intelligence tools to be designed to assist with identifying the level of beauty in human faces.
To find out more about the work process of these particular machines, we are going to explore an AI beauty analyser Pinkmirror, which determines your attractiveness score based on the analysis of your face. This tool works by automatically extracting geometric measurements of your facial features from images. The results of the analysis are based on the machine’s judgment, which was designed with the help of research and data of associated rating scores from different parts of the world.
PinkMirror beauty analysis lays the foundation on three aesthetic principles, which originate from the NeoClassical era – The “Rule of Fifths”, the “Rule of Thirds” and the “Rule of Seventy Seven”.
- The Rule of Fifths states that an aesthetically balanced face can be divided vertically into fifths which in turn are all roughly the width of one eye. In addition to that, the width of the base of the nose is equal to the distance between the eyes.
- The Rule of Thirds is based on a formula developed by Leonardo da Vinci, which states that a balanced face can be divided vertically into three equal parts. The top part starts from the hairline to the top of the eyebrows, the middle part from the top of the brows to the bottom of the nose, and the third part is from the bottom of the nose to the bottom of the chin.
Apart from Face structural analysis, there are more parameters that influence the perception of beauty. Skin health, Skin Tone, Skin Clarity, and hair management. Skin Tone: Skin quality which is mostly even across the face. Skin Clarity: Lesser spots and wrinkles. The radiance of the skin showoff the health of the person.
Face Structure Analysis
In the below two faces, which among them do you think is beautiful? For both faces, the skin quality and expressions are the same. Then what makes the difference between these two faces?
To answer this question, we studied 100,000 faces and extracted statistical information on facial features. The aspects which make a big impact on facial attraction are provided in the below table. The attractive facial features are gender specific. For female, the features that make the most impact is Bitemporal-to-Bizygomatic Ratio, Eye canthal tilt, Bigonion-to-Bizygomatic Ratio, Lower Lip Height, Chin Length-to-Philtrum Length Ratio, Chin Angle, and Mouth Width to Nose Width Ratio. For a male face, it is Bitemporal To Bizygomatic Ratio, Mouth Width To Nose Width Ratio, Nose Width, and Upper Lip To Lower Lip Ratio. Refer below table for more detailed information.
Female Attractive Features
|Feature Name||Remarks||Effectiveness||Ideal PCI Value|
|Bitemporal To Bizygoma Ratio||Larger||10||1.0415|
|Eye Canthal Tilt Angle||Larger||8.7||14.2114|
|Chin Length To Philtrum Length Ratio||Smaller||7.3||2.2876|
|Eye Width To Height Ratio||Smaller||7||2.6417|
|Interpupillary Width To Bizygomatic Width Ratio||Larger||6.7||0.4888|
|Bigonion To Bizygoma Ratio||Smaller||6.7||0.7022|
|Mouth Width To Nose Width Ratio||Larger||6.5||1.5034|
|Lip Lower Height||Larger||6.3||33.2243|
|Lip Upper Height||Larger||5.5||35.895|
|Eye Average Height||Larger||4.7||60.8911|
|Eyetobrow Inside Distance||Larger||4.4||101.3852|
|Bizygoma To Mid Face Height Ratio||Smaller||4.2||1.7199|
|Jaw Average Angle||Larger||3.5||154.7037|
|Subnasale Stomion To Stomion Chin Ratio||Larger||3.5||0.4798|
|Face Height Middle Third To Lower Third Ratio||Larger||3.4||1.6106|
|Brow Average Length||Larger||2.8||202.9699|
|Eye Average Length||Larger||2.7||153.7138|
|Brow Average Thickness||Larger||2.4||30.7468|
|Brow External Distance||Larger||2.4||575.1225|
|Eye External Distance||Larger||2.3||488.8263|
|Upper Lip To Lower Lip Ratio||Smaller||1.9||1.0769|
|Brow Average Curve Angle||Smaller||1.7||158.6125|
|Eye Internal Distance||Larger||1.7||184.3636|
|Philtrum Length To Mouth Length Ratio||Larger||1.5||0.2509|
|Eyetobrow Outside Distance||Larger||1.3||96.0725|
|Mid Face Height||Larger||1.2||400.7244|
|Nose Length To Philtrum Length Ratio||Smaller||1.2||4.013|
|Brow Internal Distance||Larger||0.9||172.5357|
|Bizygoma To Face Height Ratio||Larger||0.1||1.056|
|Lateral Canthus To Alar Angle||Smaller||0||50.2114|
Male Attractive Features
|Feature Name||Remarks||Effectiveness||Ideal PCI Value|
|Bitemporal To Bizygoma Ratio||Larger||10||1.0437|
|Mouth Width To Nose Width Ratio||Larger||8.1||1.402|
|Interpupillary Width To Bizygomatic Width Ratio||Smaller||5.9||0.4641|
|Eye Canthal Tilt Angle||Larger||5.5||7.6577|
|Eyetobrow Outside Distance||Smaller||5.4||81.8682|
|Philtrum Length To Mouth Length Ratio||Larger||5.1||0.3026|
|Lip Upper Height||Smaller||4.9||32.378|
|Chin Length To Philtrum Length Ratio||Smaller||4.4||2.3718|
|Nose Length To Philtrum Length Ratio||Smaller||3.7||3.3537|
|Upper Lip To Lower Lip Ratio||Smaller||3.7||1.1569|
|Brow Average Thickness||Smaller||3||34.8482|
|Eye Internal Distance||Smaller||3||182.6981|
|Lip Lower Height||Smaller||3||28.3403|
|Lateral Canthus To Alar Angle||Larger||2.8||50.8879|
|Eye Width To Height Ratio||Smaller||2.6||2.8973|
|Eyetobrow Inside Distance||Smaller||2.3||89.3334|
|Eye Average Height||Smaller||2||52.0301|
|Brow Internal Distance||Smaller||1.9||168.8763|
|Eye External Distance||Smaller||1.9||477.0516|
|Mid Face Height||Smaller||1.5||410.0199|
|Bizygoma To Face Height Ratio||Larger||1.5||1.0282|
|Subnasale Stomion To Stomion Chin Ratio||Smaller||1.4||0.4588|
|Eye Average Length||Smaller||1.2||147.8659|
|Bigonion To Bizygoma Ratio||Smaller||1||0.7213|
|Brow Average Curve Angle||Larger||0.7||158.4599|
|Brow External Distance||Smaller||0.6||581.904|
|Face Height Middle Third To Lower Third Ratio||Larger||0.6||1.4866|
|Jaw Average Angle||Smaller||0.3||153.6105|
|Bizygoma To Mid Face Height Ratio||Smaller||0.3||1.7309|
|Brow Average Length||Smaller||0||207.8034|
Unisex Attractive Features
|Feature Name||Remarks||Effectiveness||Ideal PCI Value|
|Eye Canthal Tilt Angle||Larger||10||12.8839|
|Bitemporal To Bizygoma Ratio||Larger||9.5||1.0428|
|Mouth Width To Nose Width Ratio||Larger||8.9||1.4774|
|Eye Width To Height Ratio||Smaller||6.8||2.6814|
|Chin Length To Philtrum Length Ratio||Smaller||6.7||2.307|
|Bigonion To Bizygoma Ratio||Smaller||5.5||0.7079|
|Upper Lip To Lower Lip Ratio||Smaller||4.4||1.092|
|Face Height Middle Third To Lower Third Ratio||Larger||4.4||1.5867|
|Bizygoma To Face Height Ratio||Larger||3.1||1.0534|
|Brow Average Thickness||Smaller||2.8||31.0712|
|Lip Lower Height||Larger||2.4||31.1745|
|Interpupillary Width To Bizygomatic Width Ratio||Larger||2.4||0.4808|
|Bizygoma To Mid Face Height Ratio||Smaller||2.4||1.7285|
|Eye Average Height||Larger||2||57.0436|
|Subnasale Stomion To Stomion Chin Ratio||Larger||1.9||0.4731|
|Eyetobrow Outside Distance||Smaller||1.5||89.8257|
|Jaw Average Angle||Larger||1.5||154.187|
|Eyetobrow Inside Distance||Larger||1.4||95.9381|
|Eye Internal Distance||Smaller||1.4||180.9958|
|Philtrum Length To Mouth Length Ratio||Larger||1.4||0.268|
|Mid Face Height||Smaller||1.1||397.11|
|Lateral Canthus To Alar Angle||Larger||1.1||50.6137|
|Brow Internal Distance||Smaller||1||168.2486|
|Eye Average Length||Larger||0.5||149.966|
|Brow Average Length||Larger||0.4||201.9581|
|Eye External Distance||Smaller||0.3||478.3444|
|Nose Length To Philtrum Length Ratio||Larger||0.2||3.8286|
|Brow Average Curve Angle||Smaller||0.1||158.5797|
|Brow External Distance||Smaller||0||568.9826|
|Lip Upper Height||Larger||0||33.8387|
The Effectiveness score is calculated based on the impact on attractiveness. This is scored separately for females and males because each feature has a different impact on each gender.
The unit used in this chart is PCI (Photographic Canthal Index).
To further evaluate the findings of this software, we are going to analyze a list of celebrities it created based on their beauty score, both males and females. We will be looking at possible reasons for listing them this way, taking into account symmetry, face shapes, skin quality, makeup, and/or other facial features.
The top 5 celebrity female faces with the highest beauty score
As we can see from the figure above, we can see that amongst the top 5 most beautiful female celebrities, the predominant shapes in the top 5 are heart and triangle. The similarities found between heart and triangle shapes are wider forehead and narrower lower part of the face, starting from cheekbones down towards the jawline.
The skin quality observed amongst the women is exceptionally smooth, with no apparent marks or distinctive characteristics.
The makeup is done in a way that complements their faces, the most common and being contouring and shading in the temple areas. This is suggested to reduce the width of the forehead for these particular shapes.
Furthermore, Shay Mitchell and Emma Watson have contour around their jawline to make it appear slimmer and reduce the sharpness. The main goal for the triangle shape is to make the face look longer and a little rounder, to balance out the proportions of the face.
On the other hand, the celebrities with the heart-shaped faces, such as Rosie Huntington Whiteley, Kate Upton, and Reese Witherspoon, have implemented slightly different techniques to enhance the overall appearance. For example, they have highlighted the jaw and chin areas with lighter foundation in order to create an illusion of more width.
Overall, their facial features and structure are symmetrical to the eye, with no extreme angles or sizes.
The top 5 celebrity male faces with the highest beauty score
The rectangle face shape is observed to be symmetrical due to the width of the forehead, cheekbones, and jawline being almost equal. In contrast, the heart shape presents prominent cheekbones, a wide forehead, and a narrow chin.
The go-to hairstyle for these particular celebrities is shorter sides and a longer top.
The overall facial build looks symmetrical to the eye with no distinctive irregularities.
Standout features that can be noted are a prominent jawline, wide forehead, and a short stubble or no beard at all.
The skin quality is smooth with no particular marks.
The shape of the face is determined by the bone structure of the skull. Furthermore, research shows that the structure and shape stem from genetic variations .
Knowing and understanding the shape of the face has become an important piece of knowledge in the beauty world. Based on your shape, you can pick out the most flattering hairstyle, a pair of glasses, and what to accent when doing makeup.
Over the years, multiple variants of shapes have been suggested as the ones that could fit the whole population of our planet. Today, scientists have identified nine distinct shapes.
Although according to various sources, the shapes and names show slight dissimilarities, the following general shapes can be outlined: round, square, oblong, heart, diamond, triangle, rectangle, pear, and oval.
If unsure which one applies to you in particular, you can figure out yours from Figure 1. There are also numerous websites and tools online that can help you figure out your face shape .
Based on the beauty score of female celebrities, the most attractive face shape for females is Triangle. Oval is a commonly accepted face shape. Heart, Round, Diamond Rectangle, and Square face shapes are generally accepted face shapes. However, Pear and Oblong face shapes are not considered attractive.
The target of the makeup/style should be as follows. Pear and Oblong face shapes need to look Oval shape to improve their attractiveness. Rest all face shapes needs to look like Triangle face shape.
Based on the beauty score of male celebrities, the most attractive face shapes for males are Rectangle and Heart. Oval, Diamond, Round, Square, and Triangle face shapes are generally accepted face shapes. However, Pear and Oblong face shapes are not considered attractive.
The target of the makeup/style should be as follows. Pear and Oblong face shapes need to look Oval shape to improve their attractiveness. Rest all face shapes needs to look like Rectangle face shape.
Find your face shape on Pinkmirror.com instantly with AI-powered tools.
Femininity vs Masculinity
Feminine and masculine facial features are generally perceived as being distinct and different from one another. Common characteristics that are often associated with feminine facial features include:
- Upturned Eyes
- An oval or triangle face shape
- Shorter Chin Length
- Thinner Eyebrows
- Longer Nose Length To Philtrum Length Ratio
- Full lips
- High cheekbones
- A smaller chin
- Large, round eyes
- Smooth, clear skin
- A smaller nose
- A narrow jawline
Some common characteristics that are often associated with masculine facial features include:
- Lower Eye Canthal Tilt
- A Rectangular face shape
- Longer Chin Length
- Thicker Eyebrows
- Shorter Nose Length To Philtrum Length Ratio
- A strong, prominent jawline
- A larger nose
- A larger brow bone
- A receding hairline
- A thicker neck
- Facial hair, such as a beard or mustache
What defines female features and male features?
|Eye Canthal Tilt Angle||Larger||Smaller||10|
|Brow Average Thickness||Smaller||Larger||8.7|
|Nose Length To Philtrum Length Ratio||Larger||Smaller||8.6|
|Philtrum Length To Mouth Length Ratio||Smaller||Larger||6.9|
|Mouth Width To Nose Width Ratio||Larger||Smaller||6.7|
|Face Height Middle Third To Lower Third Ratio||Larger||Smaller||6.6|
|Bigonion To Bizygoma Ratio||Smaller||Larger||5.4|
|Bizygoma To Face Height Ratio||Larger||Smaller||5.3|
|Upper Lip To Lower Lip Ratio||Smaller||Larger||4.7|
|Eye Width To Height Ratio||Larger||Smaller||4.6|
|Eyetobrow Outside Distance||Larger||Smaller||3.9|
|Brow Average Length||Smaller||Larger||3.7|
|Brow Average Curve Angle||Larger||Smaller||3.7|
|Interpupillary Width To Bizygomatic Width Ratio||Larger||Smaller||3.6|
|Brow External Distance||Smaller||Larger||2.8|
|Eye Average Height||Larger||Smaller||2.7|
|Lip Upper Height||Smaller||Larger||2.6|
|Mid Face Height||Smaller||Larger||2.3|
|Eye Internal Distance||Smaller||Larger||2.1|
|Eye External Distance||Smaller||Larger||1.5|
|Eyetobrow Inside Distance||Larger||Smaller||1.4|
|Subnasale Stomion To Stomion Chin Ratio||Larger||Smaller||1.4|
|Bitemporal To Bizygoma Ratio||Smaller||Larger||1.1|
|Eye Average Length||Smaller||Larger||0.8|
|Lateral Canthus To Alar Angle||Smaller||Larger||0.6|
|Jaw Average Angle||Larger||Smaller||0.5|
|Chin Length To Philtrum Length Ratio||Larger||Smaller||0.5|
|Lip Lower Height||Larger||Smaller||0.4|
|Brow Internal Distance||Smaller||Larger||0.1|
|Bizygoma To Mid Face Height Ratio||Larger||Smaller||0|
Based on the overall outcome of the analysis and measuring criteria, we can outline a few feasible reasons for the AI beauty tool to list those celebrities in that particular order.
- The skin quality is good, with no visible marks or noticeable imperfections.
- The hair and makeup choices complement the face shape.
- All the shapes have distinguishable angles. For example, a noticeable jawline, prominent cheekbones, or a pointy chin. However, they do not stand out from the overall appearance.
Apart from this, the tool itself is entertaining to use, and it could potentially give a person some insight into what their facial features signal to the outside world. Additionally, it can give people an idea of how to balance out the overall features visually with the help of makeup, hairstyles, or glasses.
Beauty has been a subject of interest for centuries. With extensive amounts of research done over the years and outlined in this study, we have learned that there is no single constructing factor that can determine whether someone can be equally attractive to every single person. Furthermore, there is no doubt that there is a wide range of new-age software that can do a lot of groundwork for humans by reading faces and extracting information.
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