The term 20/20 vision indicates that you have a visual acuity of 20/20.
It's a term only used in North America - in Europe, visual acuity 6/6 is used. These figures are based on letter charts used in a standard eye test, such as the Snellen chart.
The top number refers to the distance at which the chart is viewed (20 feet or 6 metres) and the bottom number refers to the distance at which a person with ideal vision can see a letter clearly.
So, if you have 20/40 (or 6/12) vision then you’ll just be able to see something from a distance of 20 feet that a person with perfect eyesight will be able to see from 40 feet.
Visual acuity (VA) is the measure of the ability of the eye to see from a distance various shapes and objects. Visual acuity should be measured often to spot any changes in the eye which may affect vision.
We use a letter chart to assess visual acuity, known as the Snellen test. The Snellen test was developed by Doctor Hermann Snellen in the 1860s and is what many people associate with eye tests, as it’s a commonly used piece of equipment. It features capital letters in rows of descending sizes, such as the one pictured above.
To have your eyes tested at your local store, you can book an eye test appointment here.
Book an appointmentGlasses are needed for multiple reasons, not just to correct vision.
Presbyopia is the gradual loss of your eyes’ ability to focus on nearby objects, which many people experience as they get older. People with 20/20 vision can still experience this and in most cases presbyopia treatment involves wearing prescription glasses to improve near vision.
Having 20/20 vision doesn’t necessarily mean that you can see perfectly. It’s important to remember that 20/20 vision is the standard visual acuity of normal vision – this means that from 20 feet away, you’re able to read a line on an eye chart as clearly as someone standing right in front of it. This doesn’t mean it’s the best possible vision; someone can have sight that is better or worse than this standard.
For example, in an eye test when using the Snellen chart, many young people are able to identify the smallest letters and numbers on there, which may suggest that they have 20/10 vision. This works in the same way as 20/20 vision, in that a person with 20/10 vision can see objectsat 20 feet, that a person with 20/20 vision would only be able to see at 10 feet.
Changes in your vision is just a natural part of ageing and is usually one of the first senses you’ll notice a change in as you get older. So while it’s not possible to prevent this, our experts will be able to provide some guidance about keeping your eyes as healthy as possible.
Having your eyes tested regularly is great for monitoring your eyesight and checking whether you need to wear glasses, but it’s also a really important way to make sure your eyes are healthy and to spot signs of eye conditions that could affect your vision.
Digital screens have become an integral part of our everyday lives, especially since we’ve had to adapt during the pandemic to become more digital at work, school and even socialising.
Looking after your eyes in the sun is so important. This is to protect your eyes from the UV light the sun emits, which can be very harmful to the eyelids, cornea, lens and retina. Overexposure to UV light can result in conditions like cataracts and photokeratitis.
It’s important to remember that 20/20 vision is widely regarded as ‘normal’ vision, not perfect vision. So having 20/20 vision doesn’t necessarily mean your eyesight and eye health is the best it can be. If you have had any sudden changes in your vision or you have any concerns about your eye health at any point, book an appointment and we can take a look. You can find more about what happens in an eye test and whether it’s time for your next one here.
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