20 Minute Timer
A 20 minute countdown, ready to go — press Start or Space. A good length for a nap that avoids grogginess, a HIIT session or a timed writing exercise.
- More accurate results
- Fewer clicks, keyboard friendly
- Clean, readable, works on any screen
Presets
How to use
- Pick a preset or type hours, minutes and seconds.
- Press Start (or the Space bar).
- Switch tabs freely — the remaining time is shown in the tab title.
- Press Test sound once to confirm that the browser allows audio. When time is up, the enabled alarm plays for 30 seconds.
Why this timer stays accurate
Browsers slow down background tabs to save battery, which makes timers that count “ticks” drift by seconds or even minutes. This timer stores the exact moment it should finish and compares against your device clock whenever the browser runs it, so the display catches up after a background tab, sleep or refresh instead of adding delayed ticks. Its precision is limited by your device clock; do not use a browser timer for safety-critical deadlines.
Keyboard shortcuts
Space starts and pauses. R resets to the last duration. F toggles full screen, which is handy for classrooms, presentations and workouts where the timer needs to be readable from across the room. Shortcuts are ignored while you are typing in the time fields, and “+1 min” adds a minute without stopping the countdown.
Popular timer lengths
1–3 minutes: brushing teeth, steeping tea, a plank. 5 minutes: a short break or a quick stand-up. 10–15 minutes: power naps and classroom activities. 25 minutes: one Pomodoro focus session. 30–60 minutes: exams, workouts and cooking.
Frequently asked questions
Will the alarm sound if the tab is in the background?
After you press Start or Test sound in the current page session, the timer can play its alarm while the tab is in the background. A restored timer asks you to press Test sound again because browsers require a new audio permission gesture after reload. Browsers may delay or mute background audio when a phone is locked or a device sleeps, so use the built-in clock app for a critical alarm. The tab title changes to “Time’s up!” when the page runs again.
What happens if I refresh or close the page?
A running or paused timer is saved in your browser. Reopen the page and it continues from the correct remaining time.
Can I run the timer full screen?
Yes. Click Full screen or press F. The numbers scale to fill the screen so they can be read from a distance.
What is the longest timer I can set?
Up to 99 hours, 59 minutes and 59 seconds.
Does the timer work offline?
Once the page has loaded, the timer runs entirely in your browser and does not need an internet connection.
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Updated 2026-10-19