Dominant Eye Test | Blog

Determining which of your eyes is dominant is easy to do at home. But if you need assistance, you can always ask your eye doctor. Here’s some more information on what eye dominance (or ocular dominance) is, how to test for it, and why it may be important for you to know.

A diagram showing how to test which is your dominant eye

What Is a Dominant Eye?

Your dominant eye refers to your “leading eye” or the eye that your brain naturally prefers to use. In more scientific terms, it’s the eye that sends a stronger message to the visual component of your brain.

For example, if you are right-eye dominant and you’re going to use a telescope or microscope, you would automatically look through the eyepiece with your right eye without even thinking about it. With right-eye dominance, your vision is “led” by your right eye (or vice versa if your left eye is dominant).

With some eye conditions — such as amblyopia (lazy eye) and strabismus (crossed eyes) — the “dominant eye” refers to the eye that functions more normally or is less impacted by a visual problem.

How to Determine Your Dominant Eye

Not sure which of your eyes is dominant? You can perform a basic assessment at home by following a few simple steps:

Hold your arms out in front of you and create a triangular shape between your two thumbs and two pointer fingers.
While keeping both eyes open, center or frame the triangle shape you’ve created around a distant object, such as a doorknob or light switch.
Bring the “triangle” of your hands closer to your face.
Now, close your left eye and keep your right eye open.
If the object you chose was centered in the triangle while only your right eye was open, you are right-eye dominant.
If the object appeared outside the triangle while only your right eye was open, you may be left-eye dominant.
Now try again. This time, close your right eye and leave your left eye open.
If the object you chose remained centered in the triangle while only your left eye was open, you are left-eye dominant.

Basically, your dominant eye is the one that makes the object appear centered between your thumbs and pointer fingers when only that eye is open.

While this experiment is generally considered accurate, your dominant eye can sometimes be affected by which of your hands is dominant. You can try some of the other eye dominance tests available online, but your eye care professional will be able to give you the most precise results.

Do You Need a Dominant Eye Test?

You may not need a dominant eye test unless there is a specific problem in one of your eyes or if your doctor is considering monovision for you with a procedure or contact lenses (more on that later). It can be useful information for them to have if you need special treatment for a specific condition.

Your eye doctor may perform a dominant eye test to help diagnose and treat certain eye problems, including:

Amblyopia

This condition causes reduced vision in one eye due to the way vision develops in early childhood. Amblyopia can sometimes occur in both eyes, but there is usually a stronger or dominant eye that works better.

Strabismus

In this condition, the eyes are misaligned. One eye may appear “normal” while the other turns inward, outward, upward, or downward. Strabismus may occur in one eye or alternate between the two.

Presbyopia

Monovision or “blended vision” is a method of correcting presbyopia, the natural loss of near focusing ability that occurs with age. If a person with presbyopia only needs near vision correction, reading glasses will probably be all the help they need.

But if they have trouble seeing up close and far away, monovision may be a better option. It works by correcting a person’s distant vision in their dominant eye and correcting their near vision in their other eye.

The different levels of visual acuity work together to allow them to see clearly at each distance simultaneously. Monovision is accomplished with contact lenses or surgery specifically for presbyopia.

Activities for a Dominant Eye

Dominant eye tests are also a great tool if you take part in certain activities, including work and leisure. Here are some examples of careers and hobbies that benefit from knowing your dominant eye:

Science and medicine – Working in a lab, a scientist may need to use their dominant eye to look through microscopes at various specimens and cultures. A doctor will use their dominant eye to examine a patient’s ears with an otoscope and their eyes with an ophthalmoscope.
Photography – If you have a camera with a viewfinder, using your dominant eye will help with photo composition and frame placement. Using your non-dominant eye can risk subjects being out of focus or even out of the frame.
Astronomy – If you love to look at the stars at night, one of the best ways to see them is with a telescope. Use your dominant eye to look through the eyepiece for a clearer view of the sky.
Sports – If you play any sport with a physical goal or basket, you may rely more on your dominant eye to achieve accuracy — and points! Think along the lines of basketball, soccer, golf, and hockey.
Shooting and archery – Pointing and aiming for a target — whether it’s moving or not — requires a great deal of focus. Your dominant eye is key in achieving your goal.

While dominant eye tests aren’t necessary for everyone, it’s a good idea to get your overall vision health checked routinely. Contact your eye doctor for a comprehensive eye exam if it’s been a while — and if you’re curious, ask about your dominant eye!