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Online stopwatch user guide

This online stopwatch is a free, easy to use flash stopwatch which allows you to split lap times with simple one-click commands.The online stop clock displays total time, lap times (split times) and local real time. The timer allows you to split intervals, edit, delete and name the laps (splits) without interrupting the timer.  

Alarm options Illustration image

Set up single or multiple alarms. The stopwatch offers several sounds to choose from.


You can press “-“, “+” or “*” on the keyboard for Start (-) , Split (+) & Reset (*).
Hover over the question mark button Illustration image for a detailed description of each function.

Zoom/Full screen mode Show big

Click the magnifying glass to show the stopwatch in the full browser window.
Exit full screen mode by clicking the magnifying glass again. In many browsers, you can zoom further in/out by pressing Ctrl +/- (PC), ⌘ +/- (Apple/Mac). You can also use the Full screen command (F11) on the keyboard.

Name, edit and delete laps

Every action such as “Start”, “Split” and “Stop” will be appear in a list directly below the timer. You can edit the lap name or delete laps without interrupting the timer.

Note that the log is not recorded/saved by the site, so will be lost once you click “Reset” or leave the page.

How accurate is the stopwatch?

The stopwatch uses your system’s (computer/phone) internal clock to keep track of time. If your system is losing 5 seconds every hour, so will the stopwatch. If you or the system changes the system clock, the stopwatch will jump by the same amount of time.


Although the stopwatch does show milliseconds, depending on system type and system load, it may take a few moments from the click on the button or key press until this is detected by the stopwatch program.

How is the local time determined?

Based on your systems settings, the stopwatch tries to guess what would be the correct local time for you, synchronized to atomic time. Note that the synchronization takes place when the page is loaded. The system clock is later used to keep track of time, and any errors there will also be here.

In some cases, systems will have the wrong time zone setup in their system, so the local time column will show the time of that time zone instead of the correct local time for the user.