Online Stopwatch
Run a precise browser stopwatch with start, pause, reset and lap tracking.
Play Online Stopwatch
Press Start, capture laps and pause or resume whenever needed.
How to play Online Stopwatch
Press Start, capture laps and pause or resume whenever needed.
How results are calculated
Elapsed stopwatch duration and individual lap times.
Accuracy, limitations and fair comparisons
Timers may pause or be throttled when a browser tab is inactive. The challenge runs in your current browser session; compare repeated attempts on the same device for a more useful personal reference.
Questions and answers
Is Online Stopwatch free?
Yes. This activity is free and does not require registration.
Does this test upload my input or score?
No. Gameplay and optional history storage run in your browser on this device; exporting a result requires your own action.
What is the measured result?
Elapsed stopwatch duration and individual lap times.
Can the result be treated as a medical or hardware diagnosis?
No. Timers may pause or be throttled when a browser tab is inactive.
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