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.
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
- The Pomodoro technique: why 25 minutes still works
A kitchen-timer method from the 1980s is still the most reliable focus tool a developer has. Here is what the timer is actually for, and how to tune the durations.
Version 1.0.0 · Updated 2026-08-14 · Runs entirely in your browser