Stopwatch.
How this stopwatch works.
A simple, accurate stopwatch. Press Start to begin; Pause to freeze; Lap to record a split without stopping; Reset to clear everything. The display ticks at centisecond precision (0.01 second).
// WHY IT DOESN’T DRIFT
Cheap stopwatch implementations accumulate ticks via setInterval — every 100ms, they add 100 to the elapsed counter. That breaks the moment the browser throttles your tab (background tabs run at 1Hz at best) or your CPU is busy. Ours doesn’t accumulate; it anchors on performance.now() at start and computes elapsed live. Switch tabs for an hour, come back — you get the right time.
// LAP SPLITS
Each lap shows the time since the previous lap (the split) plus a running total (Σ). The fastest and slowest laps are highlighted automatically once you have at least two, so you can spot pace changes at a glance.
// USE IT FOR
- Workouts — interval training, set timing, rest periods.
- Cooking — quick precise timing for short tasks.
- Studying — measuring how long a chunk of work actually takes.
- Speed runs — anything where lap splits matter.