The 20-20-20 Rule: Does It Really Relieve Digital Eye Strain?

The 20-20-20 rule is simple: every 20 minutes, look at something about 20 feet (6 metres) away for at least 20 seconds. It’s a habit for easing digital eye strain, the tired, dry, achy feeling that comes from long stretches on a screen. It isn’t a treatment for vision problems, and it works best alongside a good screen set-up and an up-to-date prescription.

This guide explains why the rule helps, what the research actually shows, how to make it stick, and how it applies to children.

Key takeaways

Every 20 minutes of screen use, look about 6 metres (20 feet) away for 20 seconds or longer.

Distance viewing relaxes the eye’s focusing muscle, and breaks help you blink more, which eases dryness.

Studies show the rule reduces eye strain and dry-eye symptoms while you follow it, but the benefit fades once you stop.

Screen position, lighting and the right glasses matter as much as breaks. Blue light glasses aren’t recommended for eye strain.

Strain that keeps coming back can signal an uncorrected vision problem, so get your eyes checked.

What is the 20-20-20 rule?

The 20-20-20 rule (also written 20/20/20) is a break schedule for screen users: every 20 minutes, shift your gaze to something at least 20 feet away and hold it there for at least 20 seconds.

The “20”	What it means	Metric equivalent
Every 20 minutes	How often to take a break	3 breaks an hour
20 feet away	How far to look	About 6 metres
20 seconds	How long to look	Long enough to let your eyes relax

The rule was first proposed by optometrist Dr Jeffrey Anshel in the late 1990s (Modern Optometry). Today both the American Academy of Ophthalmology and the American Optometric Association recommend it.

It suits anyone who spends long stretches looking at something close: office workers, students, gamers, and children on tablets.

What is digital eye strain?

Digital eye strain is a group of eye and vision symptoms caused by long periods of screen use. It’s also called computer vision syndrome (CVS). According to the AOA, symptoms tend to get worse the longer you spend on screens, and people who use a screen for two or more continuous hours a day are at greatest risk (AOA).

Common symptoms

Tired, sore or aching eyes
Dry, gritty, watery or red eyes
Blurred vision, during or just after screen use
Headaches
Neck and shoulder pain from leaning towards the screen

Most of these symptoms are temporary and ease once you stop. But if the cause isn’t addressed, they tend to return every time you use a screen (AOA).

Why screens cause eye strain

Constant close focus. Your eyes work harder to stay focused on a near screen than on something far away.
Less blinking. People normally blink about 15 times a minute, but only about 5 to 7 times a minute on screens (AAO). Fewer blinks mean a drier eye surface.
Glare and contrast. Screen text is often less sharp than print, and reflections make it harder to see.
Distance and posture. Screens that are too close, too high or at an awkward angle add strain.
Uncorrected vision problems. Even small prescription errors, focusing problems or eye-teaming difficulties make screen work more tiring (AOA).

Why the 20-20-20 rule works

The rule works by giving the two systems that get overloaded during screen use, focusing and blinking, a regular chance to recover.

It relaxes your focusing muscle. To see a near screen clearly, a small ring of muscle inside the eye (the ciliary muscle) contracts to change the shape of the lens. Holding that contraction for hours is what makes eyes feel tired. At around 6 metres, the eye barely needs to focus at all, which is why eye charts are traditionally read at that distance. Looking that far away lets the muscle relax.

It brings your blink rate back up. Concentrating on a screen cuts blinking roughly in half (AAO). A short break, especially if you blink fully a few times, spreads fresh tears over the eye and eases dryness.

It breaks up long stretches of near work. The AOA also recommends a longer 15-minute rest after two hours of continuous screen use (AOA). Short breaks every 20 minutes make that easier to stick to.

Does the 20-20-20 rule actually work?

Yes, for symptom relief while you follow it, but the evidence suggests it eases symptoms rather than fixing their cause.

The best-known test of the rule gave 29 computer users with eye strain software that reminded them to take 20-20-20 breaks for two weeks. Their eye strain and dry-eye symptoms improved, but the improvement was gone a week after the reminders stopped. The breaks didn’t change measures of eye-teaming or the tear film itself (Talens-Estarelles et al., Contact Lens & Anterior Eye, 2023).

A 2024 study of hospital office staff in Thailand also found eye strain fell after training in the rule (Chonburi study, 2024). Other researchers have questioned whether 20 seconds is long enough, while noting that some break is better than none (Myopia Profile).

What this means in practice:

It helps while you keep doing it. Treat it as an ongoing habit, not a two-week fix.
It won’t correct a vision problem. If you need glasses, or your prescription is out of date, breaks only take the edge off.
It won’t cure dry eye disease or, on its own, prevent short-sightedness (myopia).

Not sure your prescription is up to date? Take a free 5-minute vision check.

How to make the 20-20-20 rule stick

The hardest part of the rule is remembering it, so the trick is to make breaks automatic.

Set a reminder. Use a phone timer, a 20-20-20 rule app, or a browser extension that nudges you every 20 minutes.
Pick your far point in advance. Choose a window, a far wall or a tree outside so you don’t waste the break looking for somewhere to look.
Tie breaks to natural pauses. Look away after sending an email, finishing a page, or at the end of a game level.
Blink fully during the break. A few slow, complete blinks help re-coat the eye with tears.
Stand up every couple of hours. Use the longer 15-minute rest the AOA recommends after two hours of screen use to stretch and move.

Other ways to relieve digital eye strain

Breaks help most when the rest of your screen habits are right too. These steps from the AOA and AAO address the other main causes.

Set up your screen

Place the screen 50 to 70 cm (20 to 28 inches) from your eyes, with its centre 15 to 20 degrees below eye level, so you look slightly down (AOA). If text looks too small at that distance, make the font bigger rather than leaning in.

Reduce glare and match brightness

Set screen brightness to match the room. Turn up contrast, angle the screen away from windows and overhead lights, and use a matte screen filter if glare persists (AAO).

Keep your eyes moist

Blink often. Lubricating eye drops (artificial tears) can help when your eyes feel dry; ask a pharmacist or optometrist which type suits you. If you wear contact lenses, switching to glasses for long screen sessions can reduce dryness (AAO).

Do blue light glasses help?

Probably not for eye strain. The American Academy of Ophthalmology doesn’t recommend blue light glasses for computer use, because screen-related eye strain comes from how we use screens, not the light they give off. A 2023 review of 17 trials led by the University of Melbourne found no short-term benefit for eye strain compared with ordinary lenses (Cochrane review, 2023). Night mode on your devices is a free way to cut evening blue light if sleep is your concern.

Wear the right prescription

Glasses made for driving or reading may not be sharp at screen distance. Computer glasses designed for the 50 to 70 cm range can help, especially after 40, when the eyes’ focusing range naturally shrinks. They are not the same as blue light glasses (AAO).

The 20-20-20 rule for children

Children can follow the 20-20-20 rule too, and it’s a useful screen-time habit, but for young eyes, time outdoors matters even more than breaks.

Children rarely say their eyes hurt

Kids often assume blurry or tired eyes are normal, so watch for signs instead:

Rubbing their eyes or blinking a lot during screen use
Squinting, or holding a tablet or phone very close to their face
Headaches after school or after gaming
Avoiding reading or homework, or losing their place when reading
Covering or closing one eye to see better

If you notice these, a vision screening is a sensible next step. Read our guide to pediatric vision screening

Make breaks a game

A 20-minute timer and a “spot something far away” challenge works well for younger children: name three things you can see out of the window, or count the cars in the street. Older children can use the same reminder apps as adults.

Outdoor time protects against short-sightedness

Breaks from screens ease strain, but the strongest evidence for protecting children’s long-term vision is time outdoors. In a three-year trial in Guangzhou, China, schools that added one 40-minute outdoor class a day had fewer children become short-sighted: 30.4% versus 39.5% in schools without it (Sun Yat-sen University, JAMA 2015). A 2026 meta-analysis found more outdoor time lowered myopia risk by about 25%, and pointed to roughly two hours a day as a realistic target (J Glob Health, 2026).

The 20-20-20 rule on its own hasn’t been shown to prevent myopia. Combine screen breaks with daily outdoor play.

When eye strain means you should get your eyes checked

Most digital eye strain improves with breaks and a better set-up. If it doesn’t, have your eyes checked, because uncorrected vision problems are a common cause (AOA).

Book a check if you notice:

Strain or blurred vision that doesn’t ease after rest
Frequent headaches linked to screen or reading time
Double vision
One eye that seems worse than the other
Eye pain, or eyes that stay red and dry despite breaks and drops

Check your vision in 5 minutes, free

EyeCheck’s online vision screening can show whether your eyes might need a closer look. It’s a screening, not a full eye exam: if anything is flagged, see an optometrist. Start your free vision check

Not sure when you last had a proper exam? See how often you should get an eye exam, or learn how our screening works.

Frequently asked questions

Does the 20-20-20 rule really work?

Yes, for easing symptoms. In a 2023 study, screen users who took 20-20-20 breaks for two weeks had less eye strain and fewer dry-eye symptoms. The benefit faded a week after they stopped, so it works best as a lasting habit rather than a short fix.

How long does digital eye strain last?

Usually not long. Most symptoms ease within minutes to hours of stepping away from the screen. If strain or blurred vision lasts into the next day, or returns every time you use a screen, have your eyes checked for an uncorrected vision problem.

Can digital eye strain cause headaches?

Yes. Headaches are one of the most common symptoms, along with tired eyes, dryness and blurred vision. They often come from holding close focus for long periods, glare, or posture. Frequent screen-related headaches are a good reason to get your eyes examined.

Is digital eye strain permanent?

No. Digital eye strain is a temporary discomfort, and screen use hasn’t been shown to cause permanent eye damage. Symptoms can keep coming back, though, until the underlying cause, such as poor set-up or an outdated prescription, is fixed.

Is the 20-20-20 rule good for dry eyes?

It can help. Screen use roughly halves how often you blink, and breaks give your eyes a chance to blink fully and re-wet. People with ongoing dry eye may also need lubricating drops or treatment from an eye care professional.

Should kids follow the 20-20-20 rule?

Yes. It’s an easy habit for children on tablets, phones or computers, and turning it into a game helps. For children, daily time outdoors, ideally around two hours, matters even more for protecting long-term vision.

Does the 20-20-20 rule prevent myopia?

Not on its own. There’s no good evidence that short screen breaks prevent short-sightedness. The strongest protective factor for children is time spent outdoors.

The bottom line

The 20-20-20 rule is one of the simplest ways to ease digital eye strain: every 20 minutes, look 20 feet away for 20 seconds. It works while you keep it up, and it works best alongside a good screen set-up and the right glasses. If your eyes still feel strained after a few weeks of better habits, don’t just push through. Take EyeCheck’s free vision screening and see an optometrist if anything is flagged.

Sources

This article is for general information and isn’t a substitute for advice from an eye care professional.