How can you tell if he is gay

5 Ways to Tell If a Man is Gay (Based On Science) There have been a number of scientific research studies conducted that have investigated this very hot topic. Here are some of the findings that speak to how we can decipher an individual’s sexual orientation: 1. Do His Pupils Dilate When He Looks at You? First of all, look for the bedroom eyes.

Unless you ask him directly, there's no surefire way to know if your man is gay or bi (and even then, he may not tell you). But some tell-tale signs may make you raise an eyebrow. 1. He Has Predominantly Male Friendships.