20 Second Timer — Free Tabata Countdown
Free online countdown — fullscreen, alarm, no signup
How to Use This 20 Second Timer
Set Duration
The timer is preset to 20 seconds. Click Set to confirm.
Initialize
Review the countdown display and enter fullscreen if needed.
Start
Hit Start to begin. The alarm sounds when time reaches zero.
Cast This Timer to a Bigger Screen
Mirror this countdown to any TV, projector, or display via Chromecast, AirPlay, or HDMI. Perfect for gyms, classrooms, sports facilities, or game events where everyone needs to see the same countdown.
Full casting guideCommon Uses for a 20 Second Timer
Tabata work interval (20 sec on)
The work interval at the heart of Tabata training — the most studied and replicated high-intensity protocol in sports science. Display it large on the gym monitor so athletes push through the full 20 seconds.
Handwashing and hygiene timing
The recommended handwashing duration from health authorities. Use the countdown to ensure thorough cleaning every time, especially in food service and healthcare settings.
Classroom icebreaker rounds
A quick classroom icebreaker window. Project the countdown so every student knows exactly how long they have to share their answer or introduction.
Short pitch and elevator speech practice
A standard time for short pitch practice. Use the countdown to refine your message and delivery within a tight time constraint.
Twenty seconds is the work interval at the heart of Tabata training — the most studied and replicated high-intensity protocol in sports science. It's also the recommended handwashing duration from health authorities, a classroom icebreaker window, and a standard time for short pitch practice. This 20 second timer runs large and clear in your browser from the moment you hit start. When it reaches zero the alarm fires automatically — no manual watching required. Pair it with a 10 second rest timer for a complete Tabata interval, or use it standalone for any quick timed activity. In group settings, cast it to your TV or room display so everyone sees the same countdown without crowding around a single device.
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Fun Fact
Health experts and organizations including the CDC and WHO recommend washing hands for at least 20 seconds to effectively remove germs, bacteria, and viruses. A helpful trick: singing 'Happy Birthday' twice takes approximately 20 seconds, making it a perfect timing guide. Studies show that proper handwashing for this duration can reduce respiratory illnesses by up to 21% and diarrheal diseases by up to 31%. This simple hygiene practice is one of the most effective ways to prevent the spread of infectious diseases.