Scientists at Orebro University in Sweden studied over 400 subjects to see if their personalities were linked to the irises in their eye. Their conclusions were that our eye color.

Blue Eyes

People with blue eyes can often be perceived as unassertive and timid, According to Medical Daily, they are usually perceived as "egotistical" and "competitive". Actual studies prove that they possess great inner and physical strength, and a pilot study reported by the University of Pittsburgh School of Medicine suggests that 
that women with lighter-colored eyes tend to handle childbirth stress and pain better.

Dark brown/black eyes.

You are probably a natural born leader, and if you're not, people think you are anyway! Dark brown, almost black eyes are rare, so they are perceived as secretive and mysterious, yet Medical Daily reported a study in Current Psychology that showed that people with darker eyes are generally seen as more agreeable. The darker your eyes, the more melanin is in your system. The melanin acts as an insulator for connections between brain cells. The more melanin one has, the quicker their brains may work. So maybe you could rule the world... at least, people believe you could!

Brown eyes.

Well, maybe you can't rule the world, but you still have a lot of melanin in your system, People look to you with confidence, since you tend to be agreeable and assertive. You don't agree? You think you're cranky? Another study in the journal Chronobiology International reveals that you, brown eyes, may be getting two hours less sleep than people with lighter eyes. So you are probably having a hard time getting up in the morning!

Hazel eyes

Hmmm, they are hard to describe. They usually appear to change color from green to brown, or as an iris that has two colors. They are quite unique, and people with hazel eyes tend to be spontaneous, confident and independent. The amount of melanin in the eye varies from person to person, so you can never pin down their personality, though a common theme seems to be a balanced personality that can sometimes be mysterious to read.
According to Dr. Matthew Leach of the University of South Australia, people with hazel eyes might have such mixed colors in their eyes due to materials from the bloodstream that were broken down because of liver imbalance. So they might be more prone to digestive issues.

Gray eyes

They are rare, but consider them a dimmer version of blue eyes, because they are a shade of blue. Dark gray eyes have more melanin in the front of the eyes, while paler, lighter gray eyes have less. If you have light gray eyes, you probably have to work a little harder than most people to exert yourself. Though it takes a while to break through your concerned, wary exterior, you care deeply for people who are able to get through to you. If you have dark gray eyes, you are either an exceptionally well-balanced person or there may be some kind of Jeckyll/Hyde situation going on inside you.

Green eyes

Sexy, huh? That's the way most people see you. The balance of melanin in green eyes makes them look strong and cautious, like blue eyes, but also agreeable and dominant, like brown eyes.
According to Ophthalmologist Surgeon Doctor Hamadi Kallel, people with green eyes “have an air of mystery and a quiet self-sufficiency. They are original, creative and perform well under great pressure.” A study released by the Impulse Corporation in Los Angeles on the sex appeal of eye colors revealed that green was considered sexy, and most participants who wanted to change eye color specified green as their color of choice.

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