20 Second Timer
A 20 second timer for the 20-20-20 rule — every 20 minutes, look at something about 20 feet away for 20 seconds. Press start, or hit the space bar. One-tap 20, 30 and 60 second presets, a custom duration, an optional chime and a breathing circle to rest your eyes on.
20-20-20 break
Time remaining
00:20
Every 20 minutes, look at something about 20 feet (6 metres) away until the timer reaches zero.
Space starts and pauses. Escape resets.
Duration
Options
The breathing guide is off because your system asks for reduced motion.
Changing the duration resets the countdown. Nothing you enter here is saved.
· Free
Track it in Eye Rest Reminder.
Set your interval, get a nudge on iPhone or Apple Watch when it is time to look away, and see the breaks you took on a calendar.
Why twenty seconds
The 20-20-20 rule is the standard advice for screen eye strain: every 20 minutes, look at something about 20 feet — roughly 6 metres — away for 20 seconds. The American Academy of Ophthalmology and the American Optometric Association both recommend it for anyone who spends the day in front of a screen.
Twenty seconds is a compromise between two things. Looking at something distant lets the focusing muscle that holds your eyes at reading range go slack, and a pause away from the screen gives you time to blink properly — screen work cuts how often you blink, which is a large part of why eyes feel dry and gritty by mid-afternoon. Twenty seconds covers both and is short enough that you will actually take the break.
The numbers are round because round numbers get remembered, not because nineteen seconds fails and twenty-one works. Treat the countdown as a prompt to look away and blink, and do not worry about the last second.
The 20-20-20 rule is a widely recommended habit rather than a clinically derived threshold. Evidence for these exact figures is limited, and the studies that do exist measure comfort rather than eye health. If your eyes hurt, your vision blurs, or the symptoms carry on after you take breaks, see an optometrist or ophthalmologist.
American Academy of Ophthalmology: Computers, Digital Devices and Eye Strain ↗American Optometric Association: Computer Vision Syndrome ↗
20 second timer FAQ
What is the 20-20-20 rule?
Every 20 minutes of screen work, look at something about 20 feet — roughly 6 metres — away for 20 seconds. It is the break pattern recommended by the American Academy of Ophthalmology and the American Optometric Association for digital eye strain.
Why 20 feet?
From about 20 feet outward, the focusing muscles in your eyes are close to fully relaxed, so anything at that distance or beyond does the job. You do not need to measure it — a window, a far wall or the end of a corridor is enough.
Do screen breaks prevent eye damage?
No, and they do not need to. Screen use leaves eyes tired, dry and irritated; there is no good evidence that ordinary screen time causes permanent damage. Breaks ease the discomfort you actually get, rather than protecting you from an injury that is not happening.
What if I keep forgetting to take breaks?
Most people do — the hard part is remembering the 20-minute interval, not sitting through the 20 seconds. Use a repeating reminder or an app that prompts you on a schedule, and treat a missed break as normal rather than a failure.
Can I use this as a plain 20 second timer?
Yes. Pick 20, 30 or 60 seconds or type your own duration, press start, and press the space bar to pause or Escape to reset. The countdown is worked out from the clock rather than counted in ticks, so switching tabs does not slow it down, and nothing you enter is saved.