In order to be legally blind, you must have a visual acuity of 20/200. This means that even with glasses or contacts, you can only read the first letter at the top of the Snellen Chart, if that. You can also be legally blind if you can see, but only in a very small window in your eye.

To be considered "legally blind" in the United States and many other countries in 2026, a person must meet one of two specific clinical criteria. First, their visual acuity must be 20/200 or worse in their better-seeing eye while wearing the best possible corrective lenses (glasses or contacts). This means that a legally blind person must be at 20 feet to see what a person with "normal" vision can see from 200 feet away. The second criterion involves the field of vision; if a person's peripheral vision is severely restricted to an angle of 20 degrees or less (often called "tunnel vision"), they are also classified as legally blind, even if their central vision is 20/20. It is a common misconception that legal blindness means "total darkness." Many legally blind individuals still have some usable vision and can perceive light, shapes, or colors, but their sight is limited enough that they qualify for government assistance, disability benefits, and specialized accommodations for daily living and navigation.