Online Stopwatch
Precise stopwatch measuring to hundredths of a second. Record lap splits to track individual segment times.
Online Stopwatch with Lap Times
This stopwatch measures elapsed time to hundredths of a second using JavaScript's high-resolution timing. It runs entirely in your browser with no data sent to any server.
How to Use
- Click Start to begin timing. The display updates in real time showing minutes, seconds, and hundredths.
- Click Lap while running to record a split. Each lap shows the time since the previous lap and the cumulative total.
- Click Stop to freeze the stopwatch. You can resume with Start (which becomes Resume after stopping).
- Click Reset to clear the time and all recorded laps.
Features
- Precision to hundredths of a second (0.01s)
- Unlimited lap recording with split and cumulative times
- Pause and resume support
- Accurate background timing using Date.now()
- Scrollable lap list for many entries
Frequently Asked Questions
How accurate is the online stopwatch?
The stopwatch uses Date.now() to track elapsed time with millisecond precision and displays hundredths of a second. It is accurate for general-purpose timing, including workouts, experiments, and casual use.
How do lap times work?
While the stopwatch is running, click the Lap button to record the current elapsed time. Each lap entry shows the split time (time since the previous lap) and the cumulative total time.
Does the stopwatch work in the background?
Yes. The stopwatch uses Date.now() differences to calculate elapsed time, so it continues to track correctly even if the browser tab is in the background. However, some browsers may throttle the display refresh.
Related Tools
Countdown Timer · Count Up Timer · Interval Timer · Pomodoro Timer