Just like we use one side of our body more than the other and have a dominant hand that we use for writing, most of us also have a dominant eye.

A dominant eye isn’t always about one having better vision, but rather one leading better than the other because of preference. Your dominant eye is the one that provides slightly more input to the visual cortex of your brain and relays information more accurately, such as the location of objects.

Research shows that eye dominance and handedness are associated, though not directly related. Someone who is right-handed is more likely to be right-eye dominant, but it is possible to be right-handed and left-eye dominant.

Eye dominance can vary from person to person. One person may have strong degree of dominance in one eye, while another person may have an eye with a lesser difference in dominance from the other eye.

There are three different type of eye dominance that is determined by special tests used to find the dominant eye:

types of eye dominance
  • Sighting dominance. This is the preference of one eye over the other when fixating on a target.
  • Motor dominance. This refers to the eye that is less likely to lose fixation at the near point of convergence.
  • Sensory dominance. This refers to the eye that has stronger vision than the other.

Since hand dominance doesn’t necessarily correspond with eye dominance, using a dominant eye test is the only way to find your dominant eye.

There are different types of tests to help you find your dominant eye, though some evidence suggests that results can vary from test to test depending on distance.

If you’d like to give it a try, here are some simple tests to help you find your dominant eye.

Targeting or point test

This test involves fixating on a target and pointing at it with your index fingers to establish your dominant eye.

how to perform a target test
  1. Choose a target in the distance, such as a picture hanging on a wall or vase on a table.
  2. Point at the target using both of your two hands. Your hands should be intertwined with your two index fingers together, pointing at the target.
  3. Take turns closing each eye while fixating on the target.

Result: The eye that is lined up with the target is your dominant eye.

Hole-in-the-card test

The hole-in-the-card dominant eye test involves viewing a distant target through a rectangular card with a small hole in it.

how to perform a hole-in-the-card test
  1. Cut a hole in the center of a rectangular card, such as a playing card, or small piece of paper. The hole should be approximately 1.25 inches (3 cms) in diameter.
  2. Pick a distant object to fixate on.
  3. Hold the card in front of you at arm’s length and view the target. Take turns closing each eye or have someone else place their hand over your eye while you view with the other.

Result: The eye that sees the target through the hole is your dominant eye.

Thumb test

This simple test involves looking at a target with your thumb in front of the target.

how to perform a thumb test
  1. Extend one arm out in front of you with your thumb in the upright position.
  2. Use both your eyes to focus on a distant object and move your arm so that your thumb is the center of your view of the object.
  3. Close one eye at a time.

Result: The eye that keeps your thumb directly in front of the object while the other is closed is your dominant eye.

Knowing which eye is your dominant eye can improve your performance in certain sports and activities, such as photography.

Sports

In some sports, being able to take full advantage of your dominant eye is crucial and requires positioning your head properly in order to do so. Golf and baseball are two examples of this.

In golf, turning your head to use your dominant eye is key in the proper alignment of every stroke, including putts, drives, and fairway shots.

In baseball, you need to turn your head enough to allow your dominant eye to clearly see the approaching ball’s position, rotation, and speed when you’re batting if you want to be able to hit it.

Shooting

Your dominant eye plays an important role in shooting and hitting moving targets. If you find that you’re having trouble hitting moving targets, you can benefit from a test to find your dominant eye.

Cross dominance, which is having a dominant eye on the opposite side of your dominant hand, can make shooting at a target difficult. Being aware of your cross dominance can help you adjust position and technique, and know which eye to fixate with to improve your accuracy.

Photography

Knowing which of your eyes the dominant eye can help you set up a shot when looking through the viewfinder of a camera. By using your dominant eye, you get a more accurate preview of the shot and better alignment, while using your non-dominant eye can cause some details to be displaced.

Eye dominance plays a role in vision correction. It helps the doctor make clinical decisions when treating certain vision problems, such as amblyopia, which is known as lazy eye, and strabismus, or crossed eyes.

It’s also an important consideration when treating people who require different types of correction in each eye — for instance, glasses or contact lenses that correct distance vision in one eye and near vision in the other.

Eye dominance also plays an important role in planning cataract and other vision surgery. The dominant eye is often the preferred eye when setting distance during surgery. In some cases, eye dominance can change following surgery, according to a 2015 study.

Eye dominance doesn’t have any medical significance if you’re not experiencing vision problems. Figuring out your dominant eye is helpful if you engage in activities like photography, shooting, or certain sports.

Whether to improve performance or just out of sheer curiosity, there are easy tests you can use at home to find your dominant eye.