Countdown Timer

How to use

Set hours, minutes, and seconds, or choose a quick preset. Select Start, Pause, or Resume as needed. Reset stops the timer and restores the selected duration. Enable the optional sound before starting if you want an audible finish.

What this tool does

Measures time against a timestamp deadline. Returning to an inactive tab recalculates the remaining time, avoiding drift from delayed browser updates. Pausing preserves the exact remaining duration.

The timer stops when this page is closed or reloaded. A suspended browser may delay the visual update or sound until it wakes, but the deadline stays accurate. No notification permission is requested.