What Is 20/20 Vision?

Learn what 20/20 eyesight means, how visual acuity is measured, and how results such as 20/40, 20/25 and 20/20 compare.

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What does 20/20 vision mean?

20/20 is a commonly used reference measurement of distance visual acuity in the United States.

The first number represents the testing distance in feet. The second number represents the distance at which a person with reference visual acuity can identify the same level of detail.

Therefore, a result of 20/20 means that at 20 feet you can resolve detail expected to be visible at 20 feet under the test conditions.

Is 20/20 vision perfect vision?

No. 20/20 describes one aspect of vision: visual acuity.

Vision also includes color perception, contrast sensitivity, depth perception, peripheral vision, focusing ability, eye coordination and other functions.

It is more accurate to describe 20/20 as a commonly used reference level of visual acuity rather than "perfect vision."

How does 20/20 compare with other results?

Snellen result General interpretation
20/20 Common reference visual acuity
20/25 Slightly less sharp than the 20/20 reference
20/40 Detail seen at 20 feet corresponds approximately to what the reference observer may see at 40 feet
20/100 Significantly reduced distance visual acuity compared with the 20/20 reference

Can vision be better than 20/20?

Yes. Some people can identify smaller optotypes than the standard 20/20 reference.

Examples include measurements such as 20/16 or 20/15, depending on the chart and testing method.

How is visual acuity measured?

Visual acuity is commonly measured using progressively smaller letters or symbols at a standardized viewing distance.

Traditional clinical testing may use a Snellen chart or other standardized acuity systems.

PeekVision uses a browser-based screening approach to help users estimate visual acuity for the right eye, left eye and both eyes.

What is logMAR?

logMAR is another way of expressing visual acuity and is commonly used in research and clinical measurement.

A logMAR value of approximately 0.0 corresponds to 20/20 visual acuity. Larger positive values generally represent reduced acuity, while negative values represent acuity better than the 20/20 reference.

Can I check 20/20 vision online?

An online test can provide preliminary screening information, but results depend on viewing distance, screen size, browser rendering, display scaling and test conditions.

A professional examination provides more controlled and comprehensive assessment of your eyes and vision.

Try the PeekVision visual acuity screening

PeekVision allows you to screen the right eye, left eye and both eyes directly in your browser.

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When should you have a professional eye examination?

Consider professional eye care if your screening result is reduced, your two eyes differ noticeably, your vision has changed, or you have ongoing concerns about your eyesight.

Sudden vision loss, severe eye pain, flashes, new floaters, a curtain-like shadow in vision or eye injury may require prompt medical attention.

Important limitation

PeekVision provides informational vision screening only. It does not diagnose refractive error, eye disease or other medical conditions and does not replace an examination by an optometrist or ophthalmologist.

Want to compare 20/20 with logMAR or decimal visual acuity? See the Snellen to logMAR conversion chart .