Fullscreen Countdown Timer
A focused countdown timer with fullscreen mode.
Set the duration
Good to know
- Time is anchored to an absolute timestamp, so it stays accurate even if the tab throttles.
- Pause keeps the remaining time; Reset clears everything.
- On iOS, fullscreen works from the button — Safari may require a tap first.
Fullscreen countdown
Countdown
05:00
Ready
Fullscreen shows only the clock — ideal for workouts, talks or study blocks. The timer keeps running while paused elsewhere in the tab; screen wake lock is requested when your browser supports it.
About this tool
Run an absolute timestamp countdown for presentations, study and events. Free, private and browser-based. Fullscreen Countdown Timer runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.
What this tool does not do
- Fullscreen Countdown Timer is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.
How do I use this tool?
How do I use Fullscreen Countdown Timer?
Open Fullscreen Countdown Timer, enter or paste your input, and copy the result. The page works without an account.
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