Twenty minutes is the length of the ideal power nap and a solid focused-work block. This free 20-minute timer runs full-screen with an alarm and keeps wall-clock-accurate time in the background, so you can nap or work without watching it.
What is a 20 minute timer good for?
- The classic 20-minute power nap (wake before deep sleep)
- The 20-20-20 rule: rest your eyes every 20 minutes
- A focused reading, study or writing sprint
- A 20-minute home workout or walk
How this 20 minute timer works
Press Start and the countdown runs full-screen in your browser; press it again to pause and resume, hit Reset to return to 20 minute, or +1 min to extend. You can also press the spacebar to start or pause. It is wall-clock accurate, so it stays correct even in a background tab, and it rings when it reaches zero. Need a different length or a stopwatch and date countdown? Open the full timer.
Frequently asked questions
Is a 20-minute nap actually good?
Yes — sleep researchers consistently point to about 20 minutes as the ideal nap length. It is long enough to restore alertness and mood but short enough to wake before you enter deep slow-wave sleep, which is what causes the groggy, heavy feeling of a longer nap. Set this timer before you lie down so you do not oversleep, and add a minute or two for falling asleep if you need it. The same 20-minute interval is used in the 20-20-20 rule for reducing eye strain at a screen.
Does the timer keep accurate time if I switch tabs?
Yes — the 20 minute timer stays wall-clock accurate in a background tab. Instead of counting ticks (which browsers throttle in background tabs), it records the exact end time and works out the remaining time from your clock on every update, so the figure on screen is always correct. When you return to the tab the display instantly shows the true time left. The alarm tone is generated with the Web Audio API and plays when the countdown reaches zero with the page on screen, so keep the tab visible if you need the sound at the exact second.
Will it make a sound when it finishes? Is it free?
Yes to both — the 20 minute timer rings at zero and is completely free. When the countdown reaches zero it plays three short rising tones and the card flashes with a “Time’s up” message, so you are notified even with the sound off — use the speaker button to mute or unmute. The first time you press Start the browser unlocks audio from that tap, which is why a timer you start yourself can ring later. It runs entirely in your browser, needs no sign-up, and nothing is uploaded.
Will the 20 minute timer keep my screen awake?
The 20 minute timer does not request a screen wake lock, so a phone or laptop can still dim or lock while it counts down. The countdown itself is worked out from your device’s clock, so the time left is right the moment you look at the page again. The alarm plays when the page is on screen, so if you need to hear it at exactly twenty minutes, leave the tab visible and the screen awake, or set a phone alarm as a backup. The full timer on the main timer page does request a wake lock where the browser supports it.