Timer that beeps every 20 minutes
Beep every 20 min for 1 hr.
Space start/pause R reset Esc stop
Settings
Beep every 20 min for 1 hr.
Presets
01
What this one is for
Twenty minutes is the number in the 20-20-20 rule for screen work: every 20 minutes, look at something about 20 feet away for 20 seconds. Optometrists have pushed it for years as a way to reduce eye strain from close focus, and the reason almost nobody follows it is that you cannot notice twenty minutes passing while you are concentrating. That is the entire job of this timer.
The same interval is the standard short nap. Twenty minutes gets you the restorative part without dropping into deep sleep and waking up worse than you started, so a marker at twenty is a nap alarm you can trust more than your own sense of time.
Rest is set to 0, which means each twenty minutes runs into the next with a single tone on the boundary. Rounds sets the total, and three rounds is an hour. For a single nap alarm, set Rounds to 1.
02
Good for
- The 20-20-20 rule: look away, twenty feet, twenty seconds
- A twenty-minute nap without oversleeping it
- Standing up and moving during long desk stretches
- Rotating between two tasks on a fixed cadence
03
How it runs
Beep every 20 min for 1 hr. Press Start, or hit Space. The digits turn green while a work block runs and grey on rest.
Sound is on by default: a rising pair for work, a falling pair for rest, a tick for the last three seconds and a three-note finish. Mute with the speaker button. The screen stays on while the timer runs and the tab title shows the time left.
Change anything in Settings under the timer. The last setup you used on this page is remembered in your browser.
Questions people ask
- Is the 20-20-20 rule actually evidence based?
- It is a widely recommended habit from eye-care bodies rather than a hard finding from one trial. The mechanism it targets, sustained near focus and reduced blinking, is real; treat the exact numbers as a practical rule of thumb.
- Can I use it as a nap timer?
- Yes, with Rounds set to 1 you get one twenty-minute block and a three-note finish. Keep the tab in front and the volume up, since the sound needs the page open to play.
- Does it run while I am in another app?
- The clock keeps perfect time either way because position comes from timestamps, so you will see the correct remaining time when you return. The beep itself needs the tab open and in front, and the screen wake lock only holds while the page is visible.
- Why not just set a repeating phone alarm?
- You can, and for all-day reminders a phone alarm is the more robust tool. This is better when you want to start and stop the cadence around a work session, see the countdown, and not touch a system setting.