What Is the Purpose of the 20-20-20 Rule? How to Avoid Eye Strain

Medically Reviewed on 2/2/2022
What Is the Purpose of the 20-20-20 Rule
The purpose of the 20-20-20 rule is to minimize digital eye strain caused by staring at computers, laptops, and other devices for long periods of time

The purpose of the 20-20-20 rule is to minimize digital eye strain caused by staring at computers, laptops, tablets, smartphones, and other devices for long periods of time. 

The rule is to look at an object 20 feet away for 20 seconds every 20 minutes of screen time. This practice helps relax your eyes and minimize the damaging effect of light—including blue light—emitted from digital screens. The 20-20-20 rule may help you combat:

Following the 20-20-20 rule has the additional benefit of reminding you to take breaks during working hours.

How to follow the 20-20-20 rule

Whether you work on a computer or use your smartphone for extended hours, it can be easy to get so absorbed in your work that you forget about the 20-20-20 rule. Here are tips that can help you remember: 

  • Set a reminder on your phone every 20 minutes.
  • Enlist the help of your coworkers in following the rule.
  • Take a break whenever your eyes feel tired or fatigued.

6 ways to prevent digital eye strain

In addition to following the 20-20-20 rule, three are other ways you can avoid or prevent eye strain associated with increased screen time:

  1. Blink often: Most people blink about 15 times per minute, which helps lubricate the eyes. However, blinking tends to reduce when staring at screens to only 5-7 times per minute. This causes your eyes to become dry. Remember to blink more frequently when staring at your device to keep your eyes moist.
  2. Use artificial tears: If you have dry eyes due to excessive use of blue light-emitting devices, consider using artificial tears to lubricate your eyes. You can increase the humidity of your room by using a mist humidifier.
  3. Adjust brightness and contrast: If your screen glows brighter than your surroundings, your eyes have to work harder to see. Adjust your screen brightness to match the level of light around you. Additionally, try increasing the contrast on your screen to reduce eye strain.
  4. Cut the glare: The glare from digital screens can be reduced by using a matte screen filter, which you can purchase from an electronics store.
  5. Try computer eyeglasses or blue light-blocking glasses: If your work involves staring at a computer screen all day, you may benefit from using computer eyeglasses to minimize eye strain. These are prescription glasses that allow you to focus your eyes at a computer screen distance of 20-26 inches away from you. Blue light-blocking glasses from a good brand can also block more than 90% of the blue light emitted by devices such as computers, laptops, televisions sets, and smartphones.
  6. Sit farther away from the computer: Sit at a distance of about 25 inches (about an arm’s length) away from your computer screen. The screen should be placed so that your eye gazes slightly downward and not upward.

If your eyes feel strained even after following the 20-20-20 rule or these other tips, see an ophthalmologist.


Pink Eye (Conjunctivitis) Symptoms, Causes, Treatments See Slideshow
Medically Reviewed on 2/2/2022
Image Source: iStock Images

Computers, Digital Devices, and Eye Strain. https://www.aao.org/eye-health/tips-prevention/computer-usage