Countdown Timer
Countdown Timer counts down from any duration — set hours, minutes and seconds or tap a quick preset (1, 5, 10, 25 or 60 minutes). It flashes and plays an alarm at zero, and shows the remaining time in your browser tab so you can switch tabs while it runs.
Last updated: July 2026
A countdown timer counts down from a duration you set and alerts you at zero with a flash and an alarm sound. Set hours, minutes and seconds or tap a preset like 5 or 25 minutes, then start, pause, resume or reset. The remaining time also shows in your browser tab title.
How to use Countdown Timer
- Set hours, minutes and seconds, or tap a preset like 5 min or 25 min.
- Click Start — pause and resume whenever you need.
- At zero the display flashes and an alarm sounds.
Frequently asked questions
Does it stay accurate in a background tab?
Yes — it counts down against a fixed end time rather than ticking, so it stays accurate even when your browser throttles the tab. The remaining time also appears in the tab title.
Does it alert me when time is up?
Yes — the display flashes, shows "Time's up!" and plays a short alarm tone generated in your browser.
Is it private?
Yes — the timer and the alarm sound run entirely in your browser. Nothing is uploaded.
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