Countdown Timer — H:M:S Input, Milliseconds Display

About this Countdown

This free countdown timer runs entirely in your browser and uses the high-resolution performance.now() clock for smooth, accurate timing. Enter the hours, minutes, and seconds you need and press Start. The main display shows hours, minutes, and seconds with a live millisecond readout so you can see precisely how much time remains. You can pause or resume any time, and Reset returns the timer to the last set values in one click.

To make common durations faster, use the quick presets or the Refill Last button to restore your most recent settings. Finish cues are gentle: the timer flashes and, if enabled, plays a small chime created in the browser—no downloads or network requests. For repeating intervals, turn on Loop so the timer automatically restarts when it reaches zero.

Everything is privacy-friendly: no data is uploaded, and there are no background trackers beyond your site’s analytics. Because timing uses a monotonic clock, adjustments to the system time won’t affect the countdown’s accuracy while it runs. This makes the tool reliable for study sessions, workouts, cooking, presentations, and classroom activities where precision and simplicity matter.