How to use this tool
Press Start to measure elapsed time, Lap to record a split and Pause to stop temporarily. The stopwatch uses the browser’s monotonic performance clock, avoiding jumps caused by manual clock corrections. Displayed precision is hundredths of a second; actual scheduling and device behavior can reduce accuracy. Keep the device awake. Reset clears all lap records.
Try these values
Record a lap after each practice run. The list shows the total elapsed time at each lap and the duration since the previous lap, making it easier to compare intervals.
Laps record two useful numbers
Each lap keeps the total elapsed time and the interval since the previous lap. The total helps you follow the whole session; the interval helps you compare individual attempts. Record a lap at the end of each section without pausing, then pause when the activity itself stops. Copy the list before resetting or closing the page, because lap history is not stored.
Displayed precision is not measurement accuracy
The hundredths make short intervals easy to read, but the browser, device and the delay in pressing a button all affect the measurement. This is suitable for practice, study and everyday timing rather than certified competition or laboratory work. Keep the device awake, and check a separate timing system if losing or gaining a small fraction of a second would matter.
Common questions
What is a lap?
A lap records the elapsed time without stopping the stopwatch. The interval is the time since the previous lap.
Can I export laps?
Use Copy laps to copy a plain-text list. If clipboard access is unavailable, select and copy the visible list.
Will laps survive closing the page?
No. Copy them before leaving; this tool does not persist lap history.
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