TimerStopwatch.com

20 Second Timer

This free 20 second timer counts down 20 seconds (20 seconds) and rings an alarm at zero. It is already set — press Start or the space bar and it begins. It keeps time in a background tab, and full screen makes the digits big enough to read across a room.

00:20
Ready

Set the time

Shortcuts Space start / pause R reset F full screen + add a minute Esc stop alarm

20 seconds at a glance

Duration20 seconds
On the clock0:00:20 (h:mm:ss)
In seconds20
In milliseconds20,000
In hours0.0056
Share of a day0.02%
Start now, ends at—

What is a 20 second timer good for?

Twenty seconds is the minimum the U.S. CDC recommends for scrubbing your hands with soap — about two rounds of “Happy Birthday” — and the work interval of a classic Tabata round.

  • Hand washing: the CDC recommends at least 20 seconds of scrubbing
  • Tabata work intervals (20 seconds on, 10 seconds off)
  • The 20-20-20 eye break: every 20 minutes, look 20 feet away for 20 seconds
  • Short isometric holds

← 15 Second Timer 30 Second Timer →

How to use the 20 second timer

  1. Press Start

    The timer is already set to 20 seconds. Press Start or Space.

  2. Watch the ring

    The ring empties as time passes, and the tab title counts down with it so you can check from another tab.

  3. Adjust if you need to

    Pause any time, press +1 min to add a minute, or change the time in the panel.

  4. Stop the alarm

    At zero the alarm rings. Press Stop alarm or Esc, or +1 min to snooze.

Other quick timers

One click starts the countdown — every preset rings an alarm, works full screen and keeps time in a background tab.

Seconds

Minutes

Hours

Frequently asked questions

How do I start a 20 second timer?

Press Start (or the space bar) on this page — the timer is already set to 20 seconds. When it reaches zero the alarm rings until you stop it or the ring time you chose runs out.

How many minutes is 20 seconds?

20 seconds is about 0.33 minutes, or 20,000 milliseconds.

Why should you wash your hands for 20 seconds?

Scrubbing for at least 20 seconds gives soap time to lift dirt, grease and germs off your skin, which is why the U.S. Centers for Disease Control and Prevention (CDC) recommends it. Humming “Happy Birthday” twice takes about as long — or just start this timer.

Will the 20 second timer ring if I switch tabs?

Yes. The alarm is scheduled ahead on your browser’s audio clock, so background-tab throttling cannot delay it. Turn on notifications in the panel to get a pop-up too. If you reload the page, it keeps counting from where it was.

Can I pause the timer or add more time?

Yes. Pause stops the countdown and Start resumes it. +1 min (or the + key) adds a minute, and after the alarm it starts a one-minute snooze. To set a different length, use the time boxes, the number pad, or one of the other quick timers.

More free timing tools

Online Stopwatch Lap and split times to 1/100 s, best and worst laps, CSV export. Pomodoro Timer 25-minute focus sessions and breaks, with auto-start and a daily tally. Interval Timer HIIT, Tabata, EMOM and boxing rounds with 3-2-1 beeps and voice cues. Countdown to a Date Days, hours, minutes and seconds to any date and time zone, shareable by link. Tabata Timer20 seconds on, 10 seconds off, eight rounds — four minutes, done.

Last reviewed October 31, 2026