20/40 Vision: Understanding Your Visual Acuity
August 1, 2022 • 9:06 PM
So, you went to the optometrist for your annual eye exam, she busted out the eye chart, and you thought, “Easy!” You could rattle off letters with no problem ... until you got to that last line of letters. Suddenly, things looked a little blurry. Then the eye doctor told you that you have 20/40 vision. But what does that mean? Did you just fail your eye test?
While 20/40 vision might not be the perfect score you were hoping for, you definitely didn’t fail. But, it does mean that you have a slight case of myopia or nearsightedness — meaning you need to get closer to an item before you can see it clearly, or your near vision is better than your far vision.
We’ll walk you through what these numbers mean, what it’s like to live with 20/40 vision, and what you can do to correct your eyesight and see clearly.
What Do the Numbers in 20/40 Vision Mean?
Whether you have 20/20 vision or 20/40 vision, the numbers represent your visual acuity — or how accurately you see objects from a specific distance. In a standard visual acuity test, that distance is 20 feet, which makes up the top number in your visual acuity measurement.
The Top Number
When your doctor conducts your vision test, they’ll have you sit or stand 20 feet away from a Snellen Eye Chart (that’s the official name for the thing on the wall with all the letters). The top number in your visual acuity measurement, 20, represents that 20 foot distance — your distance from the eye chart when your eye exam was performed.
In the U.S., the top number is always 20 because it’s the standard distance for an optometry exam. But if you get your vision tested overseas, where they use the metric system, the standard distance for an eye exam will be 6 meters. So, in Canada or Australia, a person with 20/20 vision will have 6/6 vision. And a person with 20/40 vision will have 6/12 vision.
The Bottom Number
Now, onto that bottom number, which represents your distance vision compared to the “average person” or “normal person.” Your eye test is comparing how much you can see from a 20-foot distance to how much a normal person can see from a 20-foot distance.
If you have 20/20 vision, then you can see the same amount from 20 feet away as a normal person can see. But only about 35% of the population has 20/20 vision, so it’s actually more normal not to be normal.
If you have 20/40 vision, then you need to be 20 feet away to see what a normal person can see from 40 feet away. (i.e., they can stand twice as far away as you and still see everything that you can see. That sounds like an unfair advantage to us!)
Some people think that 20/20 vision is “perfect vision,” but that’s not true. It’s more accurate to call it “normal vision.” Some people have visual acuity scores that are even better than 20/20 — these people might have scores of 20/15 or 20/10. If you have 20/10 vision, then you can see things from 20 feet away that people with normal vision can only see from 10 feet away. It’s like you have super vision!
On the other end of the scale, people with really low vision have visual acuity scores that can’t be corrected to 20/20 — even with the thickest pair of eyeglasses. Some people with low vision will have 20/40 visual acuity with their glasses on. People whose vision can only be corrected to 20/200 with glasses meet the standard for legal blindness.
What’s It Like to Have 20/40 Vision?
If you’ve been living with 20/40 vision for a while, it may feel normal and you may not need corrective lenses. (Although many people find having a pair of glasses makes life easier even if they don’t use them all the time.)
Doctors will always recommend corrective lenses for patients whose visual acuity is worse than 20/40. (We’re talking scores of 20/45 and beyond.) 20/40 is that borderline score where glasses will probably improve your day-to-day life, but you’re not legally required to have them.
In the majority of states, you can pass your driver’s license exam and legally drive without glasses if you have 20/40 vision. But, it’ll take you longer to read road signs than it would take a driver with 20/20 vision. Wearing glasses while you drive will help you read those signs sooner so you never miss an exit again.
Here are a few other ways that corrective lenses can improve your daily life if you have 20/40 vision:
You’ll be able to see the chalkboard menu at your favorite cafe, even when you’re at the back of the line.
You can sit further from the whiteboard or projector screen in classes or work meetings.
You’ll see details like the subtleties of leaves on a tree better.
You’ll be able to read subtitles at the movies.
You’ll see more when you look out at a sweeping vista after a long hike or during a day at the beach.
You’ll notice more stars in the sky at night.
When you’re used to having 20/40 vision, the experience of having 20/20 vision is a beautiful thing. And if you’re worried about the look of corrective lenses, don’t be. People who wear glasses are often perceived as more honest, trustworthy, and intelligent. Plus, there are plenty of fun styles that will help you express your unique personality.
How to Improve Your Vision
If you have 20/40 vision and are longing for 20/20, there are steps you can take to improve your vision. Step one: Call your favorite optometry practice and schedule a comprehensive eye exam.
Annual eye exams are your first line of defense when it comes to your eye health. Your doctor will check for common vision problems, like nearsightedness, farsightedness, presbyopia, and astigmatism, and then prescribe corrective lenses, like single-vision or progressive lenses. They’ll also examine your retina health and check your eye pressure, and rule out serious conditions like cataracts, glaucoma, and macular degeneration.
In addition to eye exams, you can take care of your eye health by:
Addressing dry eye
Eating a healthy diet full of fruits, vegetables, whole grains, and omega-rich fish
Adding an eye care supplement that contains fish oil
But, even with proper eye care, you shouldn’t expect to wake up one day and suddenly have 20/20 vision without corrective lenses. If you have 20/40 vision, start by trying out a pair of glasses.
Options like Lasik eye surgery and contact lenses can exacerbate dry eye, and for 20/40 vision, you won’t need the ‘round-the-clock vision correction that contact lenses provide. Eyeglasses allow you to enhance your vision when you need it (like when you’re at the back of the line at that cafe), and keep your eyes working on their own the rest of the time.
A great pair of glasses is all you need to correct your 20/40 vision!
Even With 20/40 Vision, You’ve Got an Eye for Style
If you have 20/40 vision, then you need to be 20 feet away from something that people with normal vision can see from 40 feet away. That means people with 20/20 vision can see things from twice as far away as you can. Not. Fair. Even the playing field by getting a personalized pair of eyewear!
Sure, you don’t legally need glasses if you have 20/40 vision. (You can drive without them in most states.) But, life is better when you can see clearly. Plus, glasses are a fun accessory — and we never miss a chance to accessorize!
At Pair Eyewear, you can get your eyeglasses for as little as $60. Then, add stylish Top Frames that clip over the top of your Base Frames to completely change your look. Add a little sparkle, get ready for a special occasion, or have fun in the sun — without buying a second pair of frames. There’s never been a clearer choice!