About the 20-20-20 Eye Break Timer
This 20-20-20 eye break timer reminds you to rest your eyes while you work at a screen. Every 20 minutes it chimes and counts down a 20-second break, during which you look at something about 20 feet (6 metres) away; then it starts the next 20-minute block automatically. Keep the tab open, and it can also show a browser notification if you allow it.
Long periods of close-up screen work make the eye’s focusing muscles work continuously and reduce how often you blink, which can cause tired, dry or sore eyes, blurred vision and headaches — often called digital eye strain or computer vision syndrome. The 20-20-20 rule, recommended by the American Optometric Association, gives your focusing system a regular chance to relax.
Use the planner to see how many breaks a typical screen day contains and when they fall, and adjust the interval or break length if your optometrist suggests something different. Breaks help with comfort but do not correct vision problems — if symptoms persist, get an eye examination, as uncorrected prescriptions are a common cause of eye strain.
With the default inputs, the eye breaks per day is 24. Change any value above to recalculate instantly.
How to use the 20-20-20 eye break timer
- 1Set the interval and break length (20 minutes and 20 seconds by default).
- 2Press Start and keep this tab open with sound on.
- 3When the chime sounds, look at something about 20 feet away until the break countdown ends.
- 4The next 20-minute block starts automatically — use Pause for meetings away from the screen.
- 5Use the planner to see how many breaks your screen day contains.
Formula and method
The 20-20-20 rule splits screen time into blocks: after every 20 minutes of close work you spend 20 seconds looking at something about 20 feet (6 m) away. At that distance the eye’s focusing muscles are almost fully relaxed, which gives them a short recovery. The number of breaks is your screen time divided by the interval, rounded down, and each break time is the start of your day plus a whole number of intervals.
The default 20-minute interval gives 3 breaks an hour, and the 20-second break length means a full 8-hour day needs only 8 minutes of eye breaks in total. You can shorten the interval or lengthen breaks if your eyes still feel tired.
- interval
- Minutes of screen work between breaks (20 by default)
- break seconds
- Length of each distance-focus break (20 by default)
Worked examples
8-hour workday from 9:00
8 hours is 480 minutes; 480 ÷ 20 = 24 breaks, the first at 9:20 and the last at 17:00. At 20 seconds each, they total just 8 minutes.
Gaming session: 3.5 hours from 19:30
210 minutes ÷ 20 = 10.5, so there are 10 full blocks and 10 breaks, the last at 22:50. Ten 20-second breaks total about 3.3 minutes.
Longer breaks every 30 minutes
With a break every 30 minutes, an 8-hour day has 480 ÷ 30 = 16 breaks. One minute each adds up to 16 minutes of eye rest.
Frequently asked questions
What is the 20-20-20 rule?+
Every 20 minutes of screen time, look at something about 20 feet (6 metres) away for at least 20 seconds. It is recommended by the American Optometric Association to reduce digital eye strain, alongside blinking often and good screen positioning.
Does the 20-20-20 rule really work?+
Regular distance-focus breaks relax the eye’s focusing muscles and encourage blinking, and small studies of computer users have reported fewer eye-strain symptoms when such breaks are taken regularly. It eases discomfort but does not treat underlying vision problems.
What are the symptoms of digital eye strain?+
Common symptoms include tired or sore eyes, dryness or burning, blurred vision, headaches, and neck or shoulder pain. They usually ease after resting the eyes but can recur with long screen sessions.
What if I can’t see 20 feet away?+
Look out of a window or down a corridor at the farthest point available. Even looking at something across the room relaxes focusing far more than staying on the screen, which is usually only 20–30 inches away.
What else helps prevent eye strain?+
Sit about 25 inches (an arm’s length) from the screen, place it slightly below eye level, reduce glare, match screen brightness to the room, blink deliberately, and keep your glasses prescription up to date. Artificial tears can help dry eyes.
This tool gives general estimates and is not medical advice. Talk to a doctor or qualified professional about your health, diet or training.