Time Utility
Online Stopwatch
Start, pause, resume, and reset an elapsed-time stopwatch directly in your browser.
Stopwatch
Ready.
How the stopwatch works
The stopwatch records elapsed time using the browser’s monotonic performance clock and refreshes the display repeatedly while running. Pausing preserves the accumulated elapsed time so a later Start resumes from the paused value.
Worked example
Start the stopwatch and let it run for about five seconds. The display should advance from 00:00:00.00 to approximately 00:00:05.xx. Pause should hold the displayed value, Start should resume from that paused value, and Reset should return the display to 00:00:00.00.
Limitations
This is a general browser stopwatch, not a laboratory timing instrument. Background tabs, device sleep, browser throttling, and operating-system scheduling can delay screen refreshes. The underlying elapsed-time calculation uses the performance clock, but the visible display should not be treated as certified timing equipment.
Privacy
No server request is needed to measure the interval. The timer state stays in the browser tab.
Common questions
Does Pause lose elapsed time?
No. Pause stores the elapsed interval, and Start resumes from that value.
What does Reset do?
Reset stops the stopwatch and returns the display to zero.