Stopwatch
Theme
Options
How to Use
Start
Click the green "Start" button to begin timing.
Record Laps
Click "Lap" to record split and lap times while running.
Pause / Resume
Click "Pause" to stop. Click "Start" again to resume.
Export Results
Export lap times as CSV or copy to clipboard.
Use Cases
Time running laps, swimming splits, and race segments with precision.
Track exercise sets, rest periods, and total workout duration.
Time recipes, fermentation, and brewing processes precisely.
Track speaking time with fullscreen mode for stage displays.
Measure time spent on tasks and improve efficiency.
Time experiments, reactions, and observations accurately.
Speedrun timing and competitive challenge tracking.
Timed quizzes, debate rounds, and study sessions.
Frequently Asked Questions
How accurate is this online stopwatch?
The stopwatch uses performance.now() for sub-millisecond precision, providing timing accuracy comparable to dedicated hardware stopwatches. Display updates at approximately 60fps for smooth millisecond rendering.
What is the difference between "Lap Time" and "Total Time"?
"Lap Time" shows the duration of each individual lap (time since the previous lap), while "Total Time" shows the cumulative elapsed time from the start. This is the same format used in professional sports timing.
Can I use this stopwatch offline?
Once the page is loaded, the stopwatch works entirely in your browser without needing an internet connection. All timing is done locally using JavaScript.
Is there a maximum time limit?
No. The stopwatch can run continuously for hours or even days. It uses high-resolution timing that won't drift or lose accuracy over extended periods.
How do I export my lap times?
After recording laps, use the "Export Laps (CSV)" button in the sidebar to download a CSV file, or "Copy Laps to Clipboard" to paste them directly into a spreadsheet or document.
What do the green and red badges on laps mean?
The green "Best" badge marks your fastest lap, and the red "Worst" badge marks your slowest lap. This helps you quickly identify your best and worst performance.