Spending long periods looking at a screen can strain the eyes. Using the 20-20-20 rule can help to prevent this problem. For every 20 minutes a person looks at a screen, they should look at something 20 feet away for 20 seconds.

Following the rule is a great way to remember to take frequent breaks. This may reduce eye strain caused by looking at digital screens for too long.

In this article, we describe how to use the 20-20-20 rule effectively. We also discuss the research behind the rule and other tips for preventing eye strain.

How to use the 20-20-20 rule

Alistair Berg/Getty Images

The 20-20-20 rule involves taking a 20-second break from looking at a screen every 20 minutes. During the break, a person focuses on an object that is at least 20 feet away, which relaxes the eye muscles.

The following methods can help put this rule into practice:

• Set an alarm for every 20 minutes while working, as a reminder to take a break.
• Judging a distance of 20 feet can be difficult. But looking at an object more than 20 feet away works just as well. When in doubt, aim for a longer distance rather than a shorter one.
• Look out a window during the 20-second breaks, if there is one nearby. It may be easier to find a distant object outdoors.
• Download an app developed to help people follow the 20-20-20 rule. According to the National Keratoconus Foundation, options include EyePro and Awareness.

Also, remembering to blink can prevent dry eye by encouraging tear production.

Anyone who spends the day sitting should periodically get up and walk around, to prevent back and neck pains.

What evidence supports the 20-20-20 rule?

Little scientific research has tested the effectiveness of the 20-20-20 rule, but both the American Optometric Association (AOA) and the American Academy of Ophthalmology (AAO) recommend it as a way to reduce eye strain.

Results of a 2013 study involving 795 university students suggested that those who periodically refocused on distant objects while using the computer had fewer symptoms of computer vision syndrome, which include eye strain, watering or dry eyes, and blurred vision.

In a small 2020 study, a group of patients at a university eye clinic were advised to follow 20-20-20 instructions. Twenty days later, self-reports showed no change in computer eye strain symptoms. But results of a clinical test, “tear break-up time,” indicated a significant reduction in dry eye.

Some studies indicate that taking short breaks allows the eye’s focusing muscles to relax. This may relieve eye strain.

Symptoms of eye strain

Several symptoms can indicate eye strain, including:

• eye watering
• tired or achy eyes
• blurred vision
• double vision
• dry eyes
• headaches
• eye redness

Sitting in the same position for a long time has other harmful effects on the body. For example, it can cause neck, back, or shoulder pain.

Tips for preventing eye strain

Like the 20-20-20 rule, the following methods can help to reduce or prevent eye strain:

• Use eye drops: A person blinks less than usual when using digital screens, and this can dry out the eyes. Artificial tears can be purchased at most pharmacies, as well as online. Contact lens users should check whether the product is suitable for use while wearing lenses. People with certain eye conditions may need to use preservative-free eye drops.
• Choose glasses over contacts: Consider wearing glasses instead of contact lenses during lengthy periods of computer work. Contact lenses can make dry eyes worse.
• Use a humidifier: Increasing humidity in a room that is too dry can improve dry eye symptoms. This can be done using a humidifier.
• Reduce screen glare: Protective anti-glare screens can be applied to computers, phones, tablets, and eyeglasses, to prevent eye problems. Also, flat screens tend to have less glare than curved ones.
• Check the screen’s location: The AAO recommends that a computer screen should be 25 inches (64 cm) from the eyes, about the length of a person’s arm. It is best to place the screen so that a person’s gaze looks slightly downwards.
• Adjust the screen’s contrast and brightness: Change settings so that the screen is just bright enough to read the text without straining. The right contrast may change depending on the presence of sunlight.
• Get regular eye checkups: Uncorrected vision problems are a major cause of strain. Regularly attending checkups will ensure that any changes to a person’s eyesight are addressed quickly.

These strategies can reduce eye strain related to using tablets, phones, and computers. Fortunately, most of them require little time or financial commitment.

Outlook

The 20-20-20 rule is a popular way to reduce eye strain caused by looking at digital screens for long periods.

In some cases eye strain can persist after a person has tried using the 20-20-20 rule and other methods of prevention. Anyone in this situation should see a doctor, who can check for underlying conditions such as uncorrected vision problems.

An eye doctor may need to evaluate their vision and test the level of moisture in the eyes. When making recommendations, the doctor will take a person’s occupation and overall eye health into account.

What to know about computer eye strain

• Causes
• Symptoms
• Exercises
• Other treatments
• Seeing a doctor
• Glasses
• Summary

Excessive screen time can lead to a condition called computer eye strain. This is sometimes known as computer vision syndrome, or digital eye strain. It occurs because our eyes have to work hard when viewing screens.

Many people spend long periods of time looking at their phones, tablets, computer monitors, and televisions. After all, modern jobs often require people to focus on screens for several hours per day.

On top of this, many people rely on digital media or TV to relax after work. Therefore, there is little respite for the eyes.

Keep reading to learn more about the main causes and symptoms of computer eye strain, as well as some exercises and treatment options for relieving it.

Causes

Ivan Ozerov/Stocksy

Viewing digital screens for long periods of time can make a person’s eyes work harder than usual. This can put the eyes under strain, which may lead to the development of vision problems.

As the American Optometric Association explain, the eyes are under greater strain when we view screens versus when we read printed words on a page.

This is partly because the letters on many screens are not as sharply defined as printed letters. It is also because many screens have less contrast than the printed page, and because they are affected by reflection and glare.

All of this can make a person’s eyes work extra hard when reading words on a screen.

Other factors also can contribute to computer eye strain. For example, some people view screens from inappropriate distances and angles. This can lead to the adoption of uncomfortable and tense postures, especially if the person has underlying vision problems.

Additionally, one review notes that people’s blinking rate drops dramatically when viewing screens.

However, blinking is an important biological function that keeps the surface of the eyes clean and lubricated. This reduction in blinking may also explain some of the symptoms of computer eye strain.

Symptoms

The following are some of the most common symptoms of computer eye strain:

• tired and strained eyes
• eye discomfort
• dry, irritated, or burning eyes
• blurred vision when viewing screens or looking into the distance
• difficulty refocusing the eyes
• sensitivity to bright lights
• headaches
• neck and shoulder pain

Exercises

Certain exercises may help with the prevention and management of computer eye strain.

For example, the American Optometric Association recommend that people follow the 20-20-20 rule. Following this rule means looking at something that is 20 feet away for 20 seconds after every 20 minutes spent looking at a screen.

It might also be helpful to spend a little time each day on some other eye focus exercises. For example, try slowly alternating between focusing on something far away and something nearby.

Another exercise is the figure eight. This involves looking at an area of floor that is 8 feet away. Then, a person should slowly move their eyes in a figure eight shape for 30 seconds in one direction, then 30 seconds in the other.

There is some evidence to suggest that these exercises could help with computer eye strain. For example, one study has found that looking at distant objects during breaks from work can significantly reduce the symptoms of computer vision syndrome.

Some scientists have also suggested that blinking exercises may be useful in dealing with computer eye strain. For instance, some people may find that recovering a normal blinking rate when looking at screens helps alleviate some of their symptoms.

Other treatments

Other factors may help prevent and manage computer eye strain.

For instance, one article suggests that making environmental modifications could be useful. The study authors note that controlling light intensity can help reduce glare.

Additionally, different people require different light intensities to work with. For example, people over the age of 50 years may require twice the amount of light as those in their 20s.

The authors also recommend some optimum workstation arrangements. For instance, an individual’s eyes should be around 35–40 inches (in) from their computer screen. Additionally, the screen should be about 5–6 in below eye level.

When to see a doctor

Anybody whose computer eye strain symptoms are causing them significant discomfort or impairment should consider seeing a doctor or undergoing an eye exam.

Additionally, it may be worth seeking some information about local vision therapists. Vision therapists can help by providing exercises and training that may help with computer eye strain. These include focus exercises and blinking training.

Glasses

Some symptoms of computer eye strain can develop or worsen due to an underlying vision problem. Certain people may not be aware of these problems. This may be the case if they developed later in life.

If a person suspects an underlying vision problem, however, it is important that they see an eye specialist. An eye specialist can test an individual’s eyesight. This can help them determine the kinds of glasses or corrective lenses that are appropriate to the person’s needs.

Summary

Computer eye strain is a condition that is likely to become more common in the future, as more and more jobs require extended periods of screen time.

There has been comparatively little research into computer eye strain. The same is true of its prevention and management. Perhaps the only certainty about computer eye strain is that reducing screen time is likely to help.

People can try exercises, such as the 20-20-20 rule, but if the problem persists, they should see a doctor or vision therapist. There may be a more serious underlying condition at play.