Countdown timer
Set a duration, start the countdown, pause or resume it, and use fullscreen when presenting. The display follows an end timestamp rather than counting timer callbacks.
How to use
Choose a preset or enter hours, minutes and seconds. Start begins the selected duration; Pause freezes the remaining time. Reset returns to the selected duration.
Questions and answers
Will the alarm work if the device sleeps?
A background tab may update late, and sleep can delay the alarm. On resuming, the timestamp catches up. Keep the page open and the device awake for an audible alert; sound also depends on browser audio permission and volume. Clock changes can affect this wall-clock timer.
Checks and limits
Checked: a 3-second countdown completes, pause/resume preserves remaining time, a simulated 10-second callback delay catches up, and invalid minutes are rejected.
Automated Chromium checks covered working controls, invalid input, reset and mobile layout. This does not certify every browser, physical device or linguistic nuance.
Technical references
Related tools
Maintained by GadgetsFocus. Updated October 2, 2026. Implementation and translations were reviewed with AI assistance; no independent native-speaker review is recorded.