How to Use the Online Stopwatch
Click Start to begin timing. The stopwatch counts hours, minutes, seconds, and centiseconds with precision. Click Lap to record split times without stopping the clock — perfect for tracking intervals during workouts, cooking steps, or timed tasks. Click Stop to pause, and Reset to clear everything and start fresh.
All lap times are displayed in a list showing the lap number, total elapsed time, and the time difference from the previous lap. This makes it easy to compare intervals and identify patterns in your timing.
Why Use an Online Stopwatch?
A reliable stopwatch is essential for athletes timing sprints and intervals, students taking timed practice exams, cooks tracking multiple dishes, presenters rehearsing talks, and anyone who needs precise time measurement. Our online stopwatch runs directly in your browser with no installation needed — just open the page and start timing.
Unlike phone stopwatches, this tool stays visible on your screen while you work on other tasks. The lap feature makes it especially useful for interval training, where you need to track multiple segments without stopping the overall timer.
Frequently Asked Questions
How accurate is the stopwatch?
The stopwatch uses high-resolution browser timing (performance.now) and updates every 10 milliseconds, giving you centisecond precision. This is more than sufficient for most timing needs outside of professional sports.
Does it work in background tabs?
Yes. The stopwatch calculates elapsed time based on timestamps rather than intervals, so switching tabs won’t affect accuracy. When you return to the tab, the display will show the correct elapsed time.
Can I save my lap times?
Lap times are displayed on screen during your session. You can copy them manually or take a screenshot. The times are not saved between sessions since everything runs locally in your browser.
Is there a maximum time limit?
The stopwatch can run for hours without any issues. It displays hours, minutes, seconds, and centiseconds, so even long timing sessions are fully supported.
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