Stopwatch
Precision stopwatch with centisecond accuracy and lap time recording.
About This Stopwatch
This free online stopwatch provides centisecond (1/100th of a second) precision timing with lap recording capabilities. Perfect for timing workouts, races, presentations, cooking, or any activity where you need precise time measurement. The stopwatch uses requestAnimationFrame for smooth, accurate display updates.
How to Use
- Click "Start" to begin the stopwatch.
- Click "Lap" while running to record a lap time.
- Click "Stop" to pause the stopwatch. Click "Resume" to continue.
- Click "Reset" to zero out the time and clear all laps.
- The fastest and slowest laps are highlighted in green and red respectively.
Frequently Asked Questions
How accurate is this stopwatch?
The stopwatch displays centisecond precision (hundredths of a second) and uses the browser's high-resolution performance.now() timer along with requestAnimationFrame for smooth updates. Accuracy is typically within a few milliseconds.
What do the colored laps mean?
When you have recorded more than one lap, the fastest lap (shortest split time) is highlighted in green and the slowest lap (longest split time) is highlighted in red.
What is the difference between split and total time?
The "split" time shows how long each individual lap took (time since the previous lap). The "total" time shows the cumulative elapsed time from the start of the stopwatch to when that lap was recorded.
Can I use this while the tab is in the background?
The timing continues accurately even when the tab is in the background because the elapsed time is calculated from the system clock, not from animation frame counts. However, the display update rate may be reduced by the browser when the tab is not visible.