How can you spot a cheater? It’s in their face . . . and voice, scientists say.

Two new studies looked into markers of infidelity, and found that people with wide faces and suave voices were more likely to stray in a relationship.

Hmm.

The first study, conducted by Nipissing University in Ontario, found that people with larger facial width-to-height ratios (meaning wider faces) had higher levels of testosterone than their slim-faced counterparts. Researchers think those higher hormonal levels are correlated with a stronger likelihood of promiscuity, a higher sex drive and a greater willingness to have an affair.

“These findings suggest that facial characteristics might convey important information about human sexual motivations,” lead researcher Steve Arnocky says in a statement.

The second study, carried out by Albright College and Penn State University, revealed that people who had “extroverted,” articulate voices were more likely to be unfaithful.

“Extroverts show . . . greater voice quality, and fewer silent pauses,” the study, published in Evolutionary Psychology, says. “And high extroversion strongly predicts infidelity.”

The moral of the story: Keep your eyes open and your ears peeled.