Stopwatch & Countdown Timer
Precision stopwatch with laps plus a countdown timer with alarm.
About the Stopwatch & Countdown Timer
A millisecond-accurate online stopwatch with lap and split times, and a countdown timer that plays an alarm sound when it finishes. Timing uses requestAnimationFrame so it stays accurate even when the tab is throttled.
Popular uses
- online stopwatch
- countdown timer
- lap timer
- timer with alarm
- stopwatch with laps
Examples
Lap timing
Start, tap Lap three timesOutput
Lap and split table with millisecond precisionKeyboard shortcuts
- Copy the main outputCtrl / ⌘ + Shift + C
- Download the resultCtrl / ⌘ + S
- Share this toolCtrl / ⌘ + Shift + S
- Reset the inputsAlt + R
- Open the tool search paletteCtrl / ⌘ + K
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Frequently asked questions
Read more
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Version 1.0.0 · Updated 2026-08-14 · Runs entirely in your browser