Dr. Kendra Schmid, assistant professor of biostatistics at the University of Nebraska Medical Center, has a scientific formula.
[It's] based on 29 different points on the face. The score starts high and works its way down. Every separate calculation configures into the total: How full are your lips? Too thin lowers the score, but so does an overly thick pucker; How wide-set are your eyes? Is your nose as long as your ears? Etc.
At the end you get a score between 1 and 10 — 10 being the perfect face. Most people, i.e. non-Hollywood normals, score around 4 and 5. Celebrities rarely, if ever, score below a 6.
Brad Pitt weighs in at an impressive 9.67.