Eyewear and Vision
20-20-20 eye break timer.
Start the timer and it counts down 20 minutes of screen work, then a 20-second look-away break, then repeats. A soft beep is optional. Keep this tab open; runs in your browser and nothing is sent or stored.
Timer settings
Timer
Press Start timer to begin.
The short answer
The 20-20-20 rule: every 20 minutes of screen use, look at something 20 feet (about 6 metres) away for at least 20 seconds. This page times it for you.
Worked example
With the default 20 minutes and 20 seconds, one cycle is 20 min 20 s. In an 8-hour screen day that is 23 breaks, adding up to 7 minutes 40 seconds of look-away time. Change the numbers if you prefer shorter work blocks or longer breaks.
How it works
The American Optometric Association's advice for digital eyestrain is the 20-20-20 rule: take a 20-second break to view something 20 feet away every 20 minutes. The same AOA page also suggests resting the eyes for 15 minutes after two hours of continuous computer use. Twenty feet is 6.096 metres, so across a room or out of a window is fine.
The timer counts real elapsed time, so it stays accurate if the tab is in the background, though browsers may delay the beep or the title update in a hidden tab. Keep the tab open. It does not use notifications, camera or any account.
What this is not. It does not test your eyes, and it makes no claim about blue light. Persistent eye strain, headaches or blurred vision are reasons to book an eye exam.
Sources (opened 2026-10-08): American Optometric Association, Computer vision syndrome.
FAQ
What is the 20-20-20 rule?
Every 20 minutes of screen time, look at something 20 feet away for at least 20 seconds. The American Optometric Association gives it as advice to help with digital eyestrain.
How far is 20 feet?
About 6 metres (exactly 6.096 m). Looking across a room or out of a window works.
Does the timer work in a background tab?
It measures real elapsed time, so the countdown stays right, but your browser may delay the beep or the tab title update in a hidden tab. Keep the tab open for best results.
Can I change the intervals?
Yes. Set any work block from 1 to 120 minutes and any break from 5 to 600 seconds.
Does this fix blue light problems?
This timer only schedules breaks. It makes no claims about blue light.
When should I see an eye doctor?
If you have lasting eye strain, headaches or blurred vision, book an eye exam. A timer does not replace one.
Disclaimer
Not medical advice. A break timer is a habit aid, not treatment. See an eye-care professional about eye strain, headaches or changes in vision.