A symmetrical face is one whose left and right halves are close to mirror images. Research finds that more symmetrical faces are rated a little more attractive on average, but the effect is modest, and perfectly symmetrical faces often look unnatural. You can see how symmetrical your own face is with our free face symmetry test.
What a symmetrical face is
Draw a line down the middle of a face, through the forehead, the bridge of the nose, the lips and the chin. In a perfectly symmetrical face, every point on one side would have a twin at the same height and the same distance from that line on the other side.
No real face works that way. The eyes sit at slightly different heights, one brow arches a little more, the nose leans a fraction to one side, one corner of the mouth lifts more in a smile. These differences are completely normal.
Is a symmetrical face more attractive
Research says yes, a little. In a review of the field, psychologist Gillian Rhodes found that symmetry, averageness and typical sex differences are each attractive in both women and men, and across cultures. Studies that make faces more or less symmetrical on a computer usually find that people prefer the more symmetrical version, on average.
There are three important caveats.
- The effect is modest. Symmetry explains only a small part of why people find a face attractive. Expression, skin, grooming, familiarity and personality matter a great deal more.
- Perfect symmetry looks odd. Faces made perfectly symmetrical by mirroring one half often look slightly strange or doll like. The most admired faces still have small differences between the sides.
- Averageness matters as much. Faces close to the average of many faces are rated as attractive, and averaging also smooths out asymmetry, so the two effects overlap.
How symmetrical is a typical face
We measured 201 straight on faces from public photo sets with our face symmetry test, which compares hundreds of matching points on each side of the face. The median score was 92 out of 100, and 8 in 10 faces scored between 84 and 96. Nobody scored 100.
That spread shows how normal small differences are. A score in the high eighties and a score in the mid nineties are both typical faces.
Why faces are not perfectly symmetrical
- Growth. The two sides of the face develop separately, and small differences add up from early childhood.
- Habits. Chewing on one side, sleeping on one side and favorite expressions shape the muscles and soft tissue a little over the years.
- Teeth and jaw. The bite and the position of the teeth affect the lower face.
- Age and sun. The skin and tissue on each side age at slightly different rates, often depending on which side faced the window in the car or office.
- Injury. Old breaks or injuries can leave lasting differences.
A note on health. Long standing differences are normal. A sudden change on one side of the face, such as drooping of the mouth or eyelid, needs medical attention straight away.
How to check if your face is symmetrical
By eye
- Take a straight on photo at eye level, with your head level and a relaxed face.
- Draw an imaginary line down the middle of your face.
- Compare the height of your pupils, the arch of your brows, the width of each nostril and the height of your mouth corners.
With mirrored halves
Our face symmetry test straightens your photo, finds the midline and builds two new faces, one from each half doubled. Because each half is doubled, any difference shows up twice, which is why the two faces often look like siblings rather than twins. It also gives a score for your eyes, brows, nose, mouth and jaw.
Why mirrors and selfies feel off
A mirror shows your face flipped left to right. You see that version every day, so it feels like your real face. Photos show the unflipped version, the way other people see you, and your small differences sit on the opposite sides. Our guide to mirror vs camera explains why that can feel so strange.
Symmetry and photos
Most of what changes symmetry in a photo is the photo itself.
- Head turn. Even a small turn makes the far side of the face look narrower.
- Light. Light from one side throws shadow across the other.
- Expression. Most smiles are a little uneven.
- Lens. A close camera exaggerates whichever side is nearer.
Face the camera straight on, hold it at eye level an arm length away and use soft, even light for the most balanced look.
Myths about facial symmetry
- Myth, the most attractive faces are perfectly symmetrical. Perfectly symmetrical faces made by mirroring one half often look unnatural. Admired faces still have small differences between the sides.
- Myth, asymmetry is a sign of poor health. Small, long standing differences are normal and say nothing about health. Only a sudden change needs a doctor.
- Myth, sleeping on your back will make your face symmetrical. Sleep position may play a small part in how skin creases over decades, but it does not change the bones of the face.
- Myth, the mirror shows your true face. A mirror shows your face flipped, so your small differences sit on the wrong side compared with how others see you.
How our face symmetry test measures
Our face symmetry test maps hundreds of points on your face, turns the face to look straight at the camera, then finds the midline. For every pair of matching points, it reflects one across the midline and measures how far it lands from its twin, as a share of the distance between your eyes. The average distance becomes a score out of 100, and the same measure for each feature gives the breakdown.
It also checks the mirror image of your photo and averages the two, so the face model has no lean of its own toward one side. In our tests, a mirrored copy of a photo changed the symmetry score by only about 0.2 points on average.
Symmetry in other tools
Symmetry is the largest part of our attractiveness test, worth 40 percent of the score, because it is one of the features research ties to attractiveness most consistently. Our golden ratio face test does not use symmetry, and compares proportions instead.
Symmetry is one part of a face
Symmetry is one of several ways to describe a face, along with proportions such as facial thirds and features such as high cheekbones. None of them says anything about worth. Our face tools always show their measures as geometry only, never as a judgment.