Stopwatch

Start measures elapsed time. Pause freezes it; Resume continues without counting the pause. Reset clears the time and all laps.

• Lap records only while running. The table shows the lap duration and total elapsed time, with the newest lap first. Marks use hundredths of a second; repeated clicks within the same hundredth do not create zero-time laps.
• Export CSV saves laps in chronological order. Times are seconds with a decimal point and two decimal places; headers are translated. Up to 500 laps per series.
• The stopwatch keeps running when you switch tools within this page. Only visible display updates run. Reloading or closing clears the measurement and laps; export before doing so.
• The monotonic browser clock avoids changes to the device wall clock. Displayed hundredths are resolution, not a guarantee of measurement accuracy. Click latency, browser scheduling and system sleep can affect results; sleep behavior differs between browsers and operating systems.