What is 20/20 vision?

What is 20/20 vision? The most common practised way to measure vision in a clinical setting is using standard letter charts, called a Snellen chart, with a single large letter at the top and rows of progressively smaller letters continuing down the chart.

In the United Kingdom, the standard placement of the eye chart is on a wall that’s 20 feet away from your eyes. Since many eye doctors’ rooms aren’t 20 feet long, in a smaller room the eye chart may hang behind the patient chair, using mirrors to make it appear in front of you at a simulated distance of 20 feet.

So if you can read the letters on the ’20’ line (which is the green shaded line at the lower end of the chart) from 20 feet away – then you have 20/20 eyesight.

However, most people are able to see better than 20/20 after laser vision correction. See our laser eye surgery results for more information.

According to the American Optometric Association, “20/20 vision is a term used to express normal visual acuity (the clarity or sharpness of vision) measured at a distance of 20 feet. If you have 20/20 vision, you can see clearly at 20 feet what should normally be seen at that distance. If you have 20/100 vision, it means that you must be as close as 20 feet to see what a person with normal vision can see at 100 feet.”

Can I Drive Without 20/20 Vision?

The driving standard is 20/40 where the chart letters are twice as big as those on the ’20’ line. If you have to stand at 20 feet away to be able read this bigger letters, when your normal sight friend can still pick them out from 40ft away, then you have 20/40 vision (the red back coloured line on this chart)

Please call us on 0203 733 5657 if you have any additional questions or would like to discuss vision correction or laser eye surgery in more detail.



Book a FREE* Consultation

To get a better idea of how we can help you, and also the different types of services we offer, book a free* consultation now.

Why Choose Us?

100% 20/20 vision

100% 20/20 vision

Focus Clinic has a remarkable 100% success rate for 20/20 vision. We know of no other clinic that has matched these results. There is a big difference between, for example, 98% and 100% success, especially if you are in the 2%.

Learn more
10 year guarantee

10 year guarantee

Your 10 Year Guarantee means you can return at any time if you have additional questions on the quality of your vision. If you have distance vision correction for short-sight then any repeat laser eye treatments to correct a return of myopia in the first 10 years are included free of charge.*

Learn more
Most trusted eye treatment clinic

Most trusted eye treatment clinic

We have the highest trust rating of any ‘eye treatment’ rated clinic, according to independent review site Trustpilot. With an outstanding 9.9 out of 10, when it comes to your eyes, choose the clinic that actual patients trust the most.

Learn more


*Terms and conditions apply, excludes any age-related changes and conditions unrelated to the primary treatment

Customer Reviews

Latest Posts

*Please note that there is a refundable admin fee of £25 for consultations during the week and £50 for consultations on weekends. This will be refunded to you when you attend the appointment.

Focus Clinic, 22 Wimpole Street, London W1G 8GQ, United Kingdom
Created by Digital 22