Most people have a dominant eye or one eye that works a little bit harder than the other. Even though you use both eyes to look at an object, you use your dominant eye more. You may notice this preference when you use a camera, microscope, or telescope.

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Eye Dominance and Handedness

In general, eye dominance goes along with handedness. In other words, lefties' left eyes are more likely to be dominant while righties' right eyes are likely to be dominant. But there are many exceptions to this rule. For example, according to one study, about 35% of right-handers and 57% of left-handers are left eye dominant.﻿﻿

Things get even more complicated if you're ambidextrous (a switch hitter), or use different hands for writing and throwing. According to one review, 28.8% of left-handers and 1.6% of right-handers by writing were inconsistent for throwing. For this group, it's almost impossible to correlate handedness and eye dominance.﻿﻿

Does Eye Dominance Matter?

Eye dominance has no particular medical significance, and it may make no difference in your life. It is, however, important for certain sports which require accurate aim. Archery and shooting are particularly problematic.

It is possible to change eye dominance through the use of patches and other techniques, but it is difficult and takes time. If you are considering monovision correction to reduce the need for reading glasses or bifocals, your eye dominance will need to be considered.﻿﻿

Simple Techniques

Most people automatically use their dominant eye when looking through a camera eyehole or a telescope. But you may still have a hard time deciding which eye is dominant. If you're curious, you can test yourself for eye dominance. There are several techniques for determining your dominant eye. There are tests that involve the use of a hole in a card, and others that involve the use of pinholes and rings. The Miles Test, described below, is considered to be a good indicator too.﻿﻿