What are your concerns?

Hard to understand


Or copy link


What is 20/20 Vision: What Does This Actually Say About Your Sight?

What is 20/20 Vision: What Does This Actually Say About Your Sight?

When it comes to medical terms regarding the eye, you might have already asked yourself what is 20/20 vision? It is a term that we have encountered one way or another, but perhaps never really understood. Everyone might be aware that this commonly refers to someone having “perfect eyesight.” But is it actually the case?

What is 20/20 Vision?

This term actually refers to only one aspect of having the perfect vision, which is clarity. When they say “20/20 vision,” it basically tells us that within 20 feet, we see things as they should be seen at that distance.

For example, if you see a car very clearly at 20 feet, without any prescription glasses, medications, or prior eye surgery, then that means you have a 20/20 vision. Consequently, if you have a 20/50 vision, then that means that at 20 meters, you can see things as clear as normal people will see it at 50 feet.

There’s also a chance for people to have a 20/15 eyesight, which means that they can see things at 20 feet clearer than a normal person. The misconception however is that 20/20 vision means you have perfect eyesight.

Again, it only refers to one aspect of our vision. There are still more things to consider like one’s color vision, peripheral vision, and focus vision, among others. So basically, 20/20 vision isn’t the only thing that we should look out for if we are trying to aim or even get close to that perfect vision.

Why Does My Left Eye Grade Differ from the Right?

Another question that might pop into our head when asking “What is 20/20 vision?” is why do our eyes have varying grades from each other. There are cases where some people have a higher/lower eye grade from one eye over the other.

The simple answer to that is we have different eyes. It is actually uncommon and rare to be born with equal eye grades. The majority of the people have different eye grades in their left and right eyes. This is also known as Anisometropia.

Usually, the gap isn’t that big. However, there are cases where it’s large enough to be a cause for concern especially if it isn’t addressed early on, since our brain tends to stick with the eye that has better vision, possibly completely blocking the other one out.

Signs and Causes of Visual Impairment

There are many ways to tell whether you have a visual impairment or not. The most common way is by checking your eyesight and getting a grade of 20/70 or higher. The grade 20/200 is categorized as legal blindness; but 20/70 is already an accepted criteria for low vision. Another way is if you have a fluctuating eye grade.

Having a fluctuating eye grade is actually an alarming sign as it can indicate another underlying health condition. An unstable blood sugar level and high blood pressure are only two things that cause one’s fluctuating eye grades.

Many factors also come into play in worsening vision. According to the World Health Organization (WHO), eye conditions are actually very common. One factor that causes some gradual vision impairment is aging. Over time, our eyes become less flexible which is an essential ability for it to be able to focus on an object.

Here are some other things that can cause visual impairment:

Key Takeaways

Knowing what 20/20 vision makes us understand and appreciate our eyes more. Through that, we will be able to adjust our lifestyle better. Our vision isn’t only about having that perfect eye grade. There are also other things that we have to consider in order to be able to really take care of our eyes. It may be hard to actually get that perfect vision, but our goal is to only get as close to it as possible. That is why it’s important to get our eyes checked regularly by our doctors.

Learn more about Eye Health here.

Hello Health Group does not provide medical advice, diagnosis or treatment.


Eye care, vision care, vision impairment and blindness, https://www.who.int/health-topics/blindness-and-vision-loss#tab=tab_1, Accessed March 18, 2021

Eye Exam, https://www.mayoclinic.org/tests-procedures/eye-exam/about/pac-20384655, Accessed March 18, 2021

Visual Impairment, https://kidshealth.org/en/teens/visual-impairment.html, Accessed March 18, 2021

Vaginal Acuity, https://www.aoa.org/healthy-eyes/vision-and-vision-correction/visual-acuity, Accessed March 18, 2021

Visual Impairment and Eye Care Among Older Adults, https://www.cdc.gov/mmwr/preview/mmwrhtml/mm5549a1.htm, Accessed March 18, 2021


Picture of the authorbadge
Written by Patrick Juanico Updated May 19
Medically reviewed by Victor Ephraime V. Paulino, MD, DPBO