Do humans have 20/10 vision?

Having 20/10 vision is extremely rare and considered phenomenal eyesight by many standards. This level of visual sharpness means your eyesight is better than average when tested using an eye chart from 20 feet away. But how common is this level of vision acuity in the general population and what does it really mean?

Understanding 20/10 vision

Visual acuity is measured by an eye chart test, with 20/20 vision considered normal. 20/20 means you can clearly read letters on the eye chart at 20 feet that someone with average vision could only read from 20 feet away.

20/10 vision indicates you can read letters at 20 feet that a person with normal acuity could only read from 10 feet. So 20/10 is twice as sharp as 20/20 vision.

According to experts, less than 1% of people have 20/10 visual acuity. It‘s an extremely rare level of human vision sharpness.

Other variations better than 20/20

While 20/10 is rare, other variations of vision better than the 20/20 average do exist:

• 20/12 vision: Can read letters at 20 feet that normal vision reads at 12 feet
• 20/15 vision: Can read letters at 20 feet that normal vision reads at 15 feet
• 20/16 vision: Can read letters at 20 feet that normal vision reads at 16 feet

These show progressively better than average visual acuity. 20/15 vision is estimated to be achievable by around a third of the population when corrected with glasses or contacts.

Here is a data table summarizing the visual acuity scale and distribution in the wider population:

Visual Acuity	Meaning	% of Population
20/10	Reads at 20ft what normal reads at 10ft	<1%
20/12	Reads at 20ft what normal reads at 12ft	2-3%
20/15	Reads at 20ft what normal reads at 15ft	25-35%
20/20	Normal visual acuity	60-75%
20/40	Reads at 20ft what normal reads at 40ft	Nearsighted
20/200	Legally blind	Very low %

As the table shows, only a tiny fraction have 20/10 vision, but many more can achieve 20/15 acuity or better with visual correction.

Is 20/5 vision possible?

A visual acuity score of 20/5 would mean reading letters at 20 feet that normal vision can only read at 5 feet. This extremely sharp level of vision compares to an eagle‘s visual acuity.

There have been rare reports of certain individuals, like an Aborigine man, demonstrating 20/5 visual sharpness. However, most experts believe this level of vision is likely not attainable by humans. 20/10 is thought to be the practical upper limit of human visual acuity.

Ophthalmologist Dr. Langis Michaud states: "Based on anatomy and physiology, 20/5 vision does not seem biologically possible in humans. While some animals have visual sharpness exceeding 20/10, humans do not appear to have the retinal density for such extreme visual clarity."

So while anecdotes of 20/5 vision exist, most medical experts regard 20/10 as the upper boundary under optimal conditions.

How common is 20/15 vision?

Statistics are limited, but it‘s estimated over one-third of adults can achieve 20/15 visual sharpness when wearing corrective glasses or contact lenses. A smaller percentage likely have uncorrected 20/15 vision without visual aids.

According to a large scale study on over 113,000 participants by Opternative in 2020, around 25-30% had uncorrected visual acuity of 20/15 or better. And up to 35% could reach 20/15 with glasses or contacts.

So while phenomenal 20/10 acuity is very rare at less than 1%, 20/15 vision is relatively common among the wider population with corrected vision.

Real world vision ability

What do these numbers mean in terms of real world vision ability? Here are a few examples:

• 20/13 vision: Can see clearly at 20 feet what normal vision sees at 13 feet
• 20/16 vision: Can see clearly at 20 feet what normal vision sees at 16 feet
• 20/40 vision: Can see clearly at 20 feet what normal vision sees at 40 feet

The lower the second number, the sharper the vision compared to normal. This table helps visualize the differences:

Distance	20/20 Vision	20/10 Vision
10 feet	Sees clearly	Sees very clearly
20 feet	Sees clearly	Sees very clearly
40 feet	Sees clearly	Sees moderately clearly
100 feet	Sees clearly	Has difficulty seeing

As shown, 20/10 vision maintains excellent visual clarity and acuity at farther distances where average vision starts to struggle.

Best vision ever recorded

Based on anecdotal evidence, the sharpest vision ever reported in a human was 20/5 in an Aboriginal individual.

At 20 feet, this person could apparently perceive fine details that most people cannot detect until 5 feet away. This extremely rare level of vision acuity compares to that of an eagle.

Ophthalmology researcher Dr. Clive Ashton states: "While scientifically unproven, isolated accounts of 20/5 vision in some Indigenous peoples like Australian Aborigines exist. If true, it would require an unprecedented retinal cell density over 40% higher than average."

So while not fully verified, 20/5 visual acuity could theoretically be possible in outliers of certain ethnic groups under optimal conditions. More research is needed.

Is 100% or 200% vision possible?

20/20 is considered 100% or normal vision. So theoretically, 200% vision would mean 20/10 acuity. As discussed above, 20/10 is thought to be the upper limit of human visual sharpness.

However, some alternative systems use percentage or decimal notation. But these still correlate to the same Snellen fractions:

• 100% vision = 1.0 = 20/20
• 200% vision = 2.0 = 20/10

So while 200% notation is sometimes used, it still refers to 20/10 visual acuity, not exceeding it. There does not appear to be any scientifically verified visual acuity in humans above the 20/10 threshold.

What is "perfect" vision?

While 20/20 is considered normal or average vision, it‘s not actually what we think of as “perfect”. Many people, especially children, have better than 20/20 sharpness.

Experts believe healthy eyes can comfortably see up to around 20/15 or 20/16 levels. So technically, someone with 20/16 vision could be considered to have “perfect” acuity better than the 20/20 average.

The U.S. Army and Air Force visual acuity standard for pilots, for example, is 20/50 or better in each eye. So 20/15 is well above the minimum benchmark, allowing for exceptional visual clarity.

Legal blindness

Visual acuity below 20/200 meets the legal definition of blindness in most countries. 20/200 means reading letters at 20 feet that someone with normal vision could read at 200 feet away. Extremely poor vision.

To be legally blind, this level of visual sharpness must not be improvable with corrective lenses. Many with 20/200 acuity or worse can see reasonably well with properly prescribed glasses or contacts.

According to the World Health Organization, over 1.3 billion people worldwide live with some form of distance vision impairment. Of those, around 36 million are classified as legally blind.

So while defined as blind, many in this category still maintain functional vision with visual aids.

Severe vision loss

The visual acuity scale also classifies levels of severe vision impairment:

• 20/200 to 20/400: Severe vision loss
• 20/500 to 20/1000: Profound visual impairment
• Less than 20/1000: Near-total visual impairment

As the numbers indicate, someone with 20/500 vision would have to be at 20 feet to read letters an average person could read at 500 feet.

Severe visual impairment has significant impacts on daily living. Difficulty seeing faces, reading, walking on uneven ground, and performing fine detail work are common. Vision rehabilitation training and magnification devices can help optimize remaining vision.

According to a 2020 study, around 216 million people worldwide have severe vision impairment or worse. However, the prevalence varies significantly by region.

Very poor vision examples

Here are some examples of bad visual acuity scores and what they mean:

• 20/40 vision: Can see at 20 feet what normal vision sees at 40 feet. Mild nearsightedness.
• 20/200 vision: Can see at 20 feet what normal vision sees at 200 feet. Legally blind.
• 20/400 vision: Can see at 20 feet what normal vision sees at 400 feet. Severe impairment.

The higher second number indicates worse visual acuity compared to normal vision. This table summarizes acuity scores:

Visual Acuity	Classification
20/40	Mild vision impairment
20/70	Moderate vision impairment
20/200	Legal blindness threshold
20/400	Severe vision loss
20/1000	Extremely low vision

As shown, mild impairment starts at 20/40, worsening incrementally on the scale.

The poorest vision

The worst human visual acuity is less than 20/1000 vision. This is classified as near-total visual impairment or near-total blindness.

At this level, the person can only read letters at 20 feet that someone with average vision could read from over 1000 feet away. They may only be able to detect light, colors, shapes and movement.

According to the WHO, around 5.1% of global cases of distance vision impairment are classified as near-total blindness. However, prevalence varies from around 1% in developed regions to 8% in developing countries.

Ethnicity factors

Studies suggest certain ethnicities, such as some Aboriginal peoples, may have naturally better visual acuity compared to European populations. One study found Aborigines as a group had significantly better eyesight.

Researchers believe this may result from differences in retinal cell density. Aboriginal groups tested have shown visual acuity levels ranging from 20/15 to the remarkable 20/5 accounts. Genetics likely explain some variations.

Ophthalmologist Dr. Rashid Al Atassi states: "Increased cone cell density in the central retina among Indigenous peoples may enable enhanced visual clarity. More research is needed, but ethnicity appears correlated to acuity variations."

So genetics and ethnicity do seem to play some role in explaining distributions of human vision ability.

Optimizing your existing vision

Can vision be improved? Unfortunately, refractive errors like nearsightedness, farsightedness and astigmatism cannot be corrected naturally. However, steps can be taken to optimize your existing visual acuity:

Eye Exercises: Eye training activities may improve focusing ability, eye coordination and reduce fatigue. Examples include pencil push-ups, eye stretches and ball tracking exercises.

Healthy Diet: Nutrition rich in vitamins A, C, E helps maintain eye health. Lutein and zeaxanthin antioxidants found in greens, eggs and oranges may also benefit vision.

Quit Smoking: Smoking increases risks of cataracts, optic nerve damage and macular degeneration.

Reduce UV Exposure: Wearing UV-blocking sunglasses helps limit sun damage to the eyes.

So while visual acuity is fixed, surrounding muscle strength, endurance and eye health can be maximized through lifestyle choices.

Vision correction methods

For refractive visual errors, options exist to improve acuity:

• Eyeglasses – Prescription lenses to correct nearsightedness, farsightedness and astigmatism. Over 1 billion globally use corrective glasses.

• Contact Lenses – Clear or colored lenses worn on the eye itself. Around 140 million use contacts worldwide.

• Refractive Surgery – LASIK, PRK and other procedures reshape the cornea with lasers. Over 35 million LASIK surgeries performed since 1991.

These treatments aim to achieve 20/20 vision or better. However, individual results and risks vary, so professional evaluation is recommended.

Advances in surgical vision correction

Refractive surgeries like LASIK have rapidly advanced in technique and safety over the past 30 years.

Early procedures often under-corrected vision, but modern LASIK now achieves 20/15 or better results in over 90% of patients. Some elite clinics even report average post-op vision nearing 20/10 levels.

Dr. Michelle Hammond, optometry researcher at UC Berkley, states: "With new wavefront and iris registration technologies, LASIK and PRK surgeries can now correct vision to 20/16 or 20/12 levels reliably. For suitable candidates, it represents an investment in maximizing visual potential."

So while still not risk-free, refractive surgeries can now achieve exceptional visual sharpness over glasses or contacts for many patients.

Optical illusions and visual acuity

It‘s important to note visual acuity only measures physiological light detection in the eye itself. Optical illusions distort the brain‘s perception of visual input from the eyes.

For example, the famous Muller-Lyer illusion looks like it has segments of different lengths, when in fact they are identical. So illusions trick the mind, not deficiencies in the eye hardware itself.

This demonstrates why visual acuity scores do not always align with perceived clarity. Our brains also interpret the visual data, creating discrepancies between measured and perceived eyesight sharpness.

Animal visual abilities

How do human eyes compare to other animals? Many creatures possess amazing visual capabilities:

• Eagles: Extremely high visual acuity estimated up to 20/5, enabling spotting prey from miles away.

• Mantis Shrimp: 12-16 color receptive cones give them the world‘s most complex color vision, seeing a spectacular array of colors.

• Cats: 6-8 times more night vision receptors allow superb nighttime capabilities.

• Dogs: Limited color but great motion sensing reaches 70-80 FPS versus human 60 FPS.

• Bees: See the full ultraviolet spectrum beyond human 400-700nm range, detecting otherwise invisible flower guides.

So while humans have impressive flexibility, many animals excel at specialized aspects of vision adapted to their environmental niches.

Aging effects on vision

Aging inevitably impacts visual sharpness over time. Presbyopia causes the eye‘s lens to gradually stiffen, making focusing on near objects increasingly difficult.

Onset is common in the early 40s, with most experiencing difficulty reading small text by age 50. Multifocal glasses can compensate but acuity still slowly declines.

Cataracts causing cloudy areas in the lens are also more prevalent with old age, further reducing vision. Good lighting, anti-glare coatings, and timely cataract surgery help counter the effects.

Conclusion

In summary, extremely rare 20/10 vision represents the upper threshold of human visual acuity under optimal conditions. While 20/5 may be biologically impossible, verified 20/10 is still phenomenally sharp. More modest improvements to 20/15 are relatively common with visual correction.

Unfortunately true acuity cannot be changed, but maximizing focus, health and surrounding abilities provide the best chance at experiencing your peak vision potential. I hope this deep dive on the 20/10 vision topic was an interesting read! Let me know if you have any other related aspects you are curious about.