Does the 20-20-20 rule help eye strain?

What is digital eye strain?

Digital eye strain, also called computer vision syndrome, is a group of eye and vision problems caused by long use of computers, tablets, e-readers and phones. ^[2] The most common symptoms are: ^[2]

• eye strain
• headaches
• blurred vision
• dry eyes
• neck and shoulder pain

The AOA says poor lighting, glare on the screen, the wrong viewing distance, poor posture and uncorrected vision problems can all play a part. People who spend two or more hours in a row at a screen every day are at greatest risk. ^[2]

Screens are harder on the eyes than print. Letters may be less sharp, contrast is lower, and glare can make viewing harder. ^[2] Many of the visual symptoms are temporary and fade once you stop using the screen. ^[2]

How the 20-20-20 rule works

When you look at a close screen for a long time, your eyes stay focused at one short distance. The AOA says looking into the distance for 20 seconds gives your eyes a chance to refocus. ^[2]

Breaks also help with blinking. We blink less when we stare at devices, and blink rate can drop by half. That can leave eyes dry and tired. ^[4] The AAO says this strain comes from how people use screens, not from anything the screen gives off. ^[5]

The AOA also suggests a longer rest: about 15 minutes after two hours of continuous computer use. ^[2]

During each break, blink often. The AOA advises blinking often to refresh the eyes and blinking frequently at the computer to lower the chance of dry eye. ^[6][2]

Practical suggestions (our own, not from a cited source) to help the habit stick:

• set a repeating timer for every 20 minutes
• pick a far object you can see from your desk, such as a window or a door across the room

How strong is the evidence?

The rule is advice from expert groups. Both the AAO and AOA recommend it. ^[5][2] The pages from these groups that we reviewed do not cite trials testing the rule on its own.

Research is ongoing. A trial listed on ClinicalTrials.gov compared artificial tears alone with artificial tears plus the 20-20-20 rule in screen users with dry eye. It is marked completed, but no results had been posted when we checked on 5 November 2026. ^[7]

So the fair summary is this: the rule is low-cost, low-risk and widely recommended, but its benefit on its own has not been well measured. It works best alongside the other habits below.

Myth: Using a computer damages your eyes. Fact: The AAO says computers don't harm the eyes, though long use without breaks can cause strain and dry eyes. ^[3]

Other screen habits that help

• Screen position. The AOA suggests placing the screen 20 to 28 inches from your eyes, with its center 15 to 20 degrees below eye level. ^[2] The AAO suggests about 25 inches, or arm's length. ^[4]
• Less glare. Position the screen to avoid glare from windows and overhead lights. Use blinds or a screen glare filter if needed. ^[2]
• Blink often. Blinking keeps the front of the eye moist. ^[2]
• Artificial tears. Use lubricating eye drops when your eyes feel dry. ^[4]
• The right glasses. Glasses for distance or reading may not suit screen distance. The AOA suggests telling your eye doctor about the screen distances you use at work. ^[2]
• Skip blue light glasses. The AAO does not recommend special blue light-blocking eyewear for computer use. See our blue light glasses guide. ^[5]

When to see an eye doctor

Sources

1. American Academy of Ophthalmology. “Should You Be Worried About Blue Light?” https://www.aao.org/eye-health/tips-prevention/should-you-be-worried-about-blue-light. Accessed 2026-11-05.
2. American Optometric Association. “Computer vision syndrome.” https://www.aoa.org/healthy-eyes/eye-and-vision-conditions/computer-vision-syndrome. Accessed 2026-11-05.
3. American Academy of Ophthalmology. “Common Eye and Vision Myths.” https://www.aao.org/eye-health/tips-prevention/common-eye-vision-myths-facts. Accessed 2026-11-05.
4. American Academy of Ophthalmology. “Digital Devices and Your Eyes.” https://www.aao.org/eye-health/tips-prevention/blue-light-digital-eye-strain. Accessed 2026-11-05.
5. American Academy of Ophthalmology. “Are Blue Light-Blocking Glasses Worth It?” https://www.aao.org/eye-health/tips-prevention/are-computer-glasses-worth-it. Accessed 2026-11-05.
6. American Optometric Association. “Adult Vision: 19 to 40 Years of Age.” https://www.aoa.org/healthy-eyes/eye-health-for-life/adult-vision-19-to-40-years-of-age. Accessed 2026-11-05.
7. ClinicalTrials.gov (U.S. National Library of Medicine, NIH). “20-20-20 Rule Plus Artificial Tears for Dry Eye (NCT07896395).” https://clinicaltrials.gov/study/NCT07896395. Accessed 2026-11-05.

Content reviewed against sources listed. Last reviewed 5 November 2026. This guide has not been reviewed by a clinician. Spotted a mistake? See our corrections policy.