Thirds and shape · Front photo

Left-right symmetry

No face is perfectly symmetric. Even a slightly turned head inflates this value, so it is shown for information only.

How it's measured

The face is levelled on the inner eye corners and a vertical midline is fitted through the centre points of 14 left-right pairs (temples, brows, outer eye corners, lids, pupils, cheekbones, nostril wings, mouth corners, jaw and chin points). Each right-side point is mirrored across that midline. The value is the average distance between each left point and its mirrored partner, as a percentage of cheekbone width; 0 is a perfect mirror image. One decimal, because typical values are only 1-3%.

Reference range

Male reference

0.0–3.0%

Female reference

0.0–3.0%

Source: Healthy adults differ left to right by about 3 mm or 3% on average (Farkas LG, Cheung G. Angle Orthod 1981;51:70-77).

In the score

Shown for information. It isn't part of the score.

What changes it

• Head turn or tilt changes it. Keep the head level and face the camera.

One number, one feature

One measurement describes one detail in one photo. Pose, lens and expression move it, and every reference range is an average from limited samples.