Facial Symmetry and Attractiveness: What Research Says

Every face is a little asymmetric

Look closely at any face, including the faces of people you find striking, and you will find differences between the left and right sides. One eye sits slightly higher, one side of the mouth lifts more, and the nose may bend a little. This is ordinary human anatomy. Growth, sleeping position, chewing habits, and injuries all leave small marks.

So a symmetry measurement is never asking whether a face is symmetric. It is asking how much asymmetry is present, and nearly everyone has some. The numbers describe geometry. They do not describe worth, health, or how anyone should feel.

What the research says about symmetry and attractiveness

Psychologists have studied this for decades. A few landmarks:

• Grammer and Thornhill, 1994 (Journal of Comparative Psychology). Men and women rated computer images of opposite-sex faces. The authors reported that symmetry was associated with higher ratings of attractiveness and described it as the first study to show that facial symmetry has a positive influence on attractiveness ratings.
• Rhodes, 2006 (Annual Review of Psychology). This review looked at the evidence on averageness, symmetry, and sexual dimorphism. A critical review and meta-analyses indicated that all three are attractive in both male and female faces and across cultures. The review also discussed whether these preferences are adaptations for mate choice or by-products of how the brain processes information, and argued that both may have played a role.
• Eissing and colleagues, 2024 (Journal of Personalized Medicine). In a study using 3D scans of 50 people rated by 50 evaluators, perceived symmetry and attractiveness were correlated (rho of 0.59), and the authors found no evidence that completely symmetrical faces are seen as less attractive.

The overall pattern is that more symmetric faces tend to be rated somewhat higher, on average, in these experiments. "On average" matters. The effect is modest, it varies between studies, and it says little about any one person or about how people feel about someone they know.

Perfect symmetry is not always preferred

Some earlier studies reported something different. A 1995 paper by Swaddle and Cuthill in Proceedings of the Royal Society B carried the title "Asymmetry and human facial attractiveness: symmetry may not always be beautiful." Papers like it found that slightly asymmetric faces were sometimes preferred to perfectly symmetric ones.

Research since then points to a methodology issue. Perfectly symmetric faces in many early studies were made by mirroring one half of a face, and mirroring can create odd-looking features. Rhodes and colleagues in 1998 made symmetric versions by blending a face with its mirror image and found that these versions were preferred to less symmetric ones. The 2024 study above used a different approach, averaging each surface point of a 3D scan with its mirror counterpart, and reached the same conclusion.

The fair summary is that findings are mixed in the details, but there is no strong evidence that the most symmetric faces look worse. There is also no evidence that people need to be perfectly symmetric to be attractive. Nobody is.

Averageness: the other big finding

Symmetry is only one piece. Langlois and Roggman, in a 1990 Psychological Science paper titled "Attractive faces are only average," digitized faces and mathematically averaged them. Both male and female composite faces were judged more attractive than almost all of the individual faces used to make them, and the composites became more attractive as more faces went into them.

One reason is that averaging smooths out blemishes and small asymmetries. So some of the appeal of a composite may come from smoothing and symmetry rather than averageness alone. That is a good example of how these features overlap and why researchers cannot easily pull them apart.

The Pallett, Link and Lee study, covered in our golden ratio face guide, points the same direction: the spacing people preferred matched the average face. Averageness appears more often than the golden ratio in the evidence.

Why photo symmetry scores vary

If you run a symmetry test on three photos of yourself and get three different scores, nothing is wrong. Photos are noisy. Several things move the result:

• Head turn. Turning slightly puts one side of the face closer to the camera, so the two halves no longer look equal.
• Head tilt. A study on head tilt found that tilting the head up or down shifts the brows, lids, and eye lines, so the eye-region geometry changes even when the face does not.
• Camera distance. A close camera exaggerates the nearest features, and the 2018 selfie study reported about a 30% apparent increase in nasal size at arm's length.
• Expression. Smiles are often lopsided, and raised eyebrows are rarely even.
• Hair and light. Side parts, shadows, and bright windows to one side change where a tool places the landmarks.

For a steadier reading, use an eye-level, evenly lit, neutral photo with your hair off your face. The photo guide on this site explains the steps, and you can run the face symmetry test on several photos and look at the spread.

What to take from all this

Symmetry, averageness, and attractiveness have a real research history, and it is interesting. It is also easy to overread. The effects are small to modest on average, depend on how stimuli were made, and tell you very little about a specific person. People respond to expression, warmth, humor, and how someone treats them far more than to a few degrees of difference between the two sides of a face.

Use a symmetry score as a curious look at geometry, not a rating. If comparing yourself to others is hurting how you feel, it is worth talking with a trusted adult or a professional.

FAQ

Are symmetric faces more attractive?

On average, studies find that more symmetric faces are rated somewhat more attractive, and a 2006 review reported that symmetry, averageness, and sexual dimorphism are attractive across cultures. The effect is modest and does not predict how any one person is seen.

Is a perfectly symmetric face the most attractive?

Results are mixed. Some early studies preferred slight asymmetry, but they may have been affected by how symmetric faces were made. A 2024 study found no evidence that completely symmetrical faces are seen as less attractive.

Is it normal to have an asymmetric face?

Yes. Nearly everyone has small differences between the left and right sides. A symmetry measurement estimates how much, not whether.

Why does my symmetry score change between photos?

Head turn, head tilt, camera distance, expression, hair, and lighting all change how the two sides of the face appear in a flat image. Use several neutral photos and compare the spread.