The stopwatch uses JavaScript's Date.now() to capture a start timestamp and calculates elapsed milliseconds on each refresh cycle (every 10 ms via setInterval). Pausing stores the accumulated time; resuming captures a new start timestamp. Lap records the total elapsed time at the moment the button is pressed. All timing runs client-side in your browser with no network calls.
For casual timing, browser stopwatches are accurate within a few milliseconds. Under heavy CPU load, the display interval may skip frames, but the underlying Date.now() calculation remains accurate. For competition-grade timing, use a dedicated hardware stopwatch.
Yes. The timer uses absolute timestamps (Date.now()), so switching tabs or minimizing the browser doesn't affect elapsed time. The display simply catches up when you return.
Use the "Copy results" button to copy all lap times to your clipboard. You can then paste them into a spreadsheet or notes app for further analysis.
A lap time is the total elapsed time when the Lap button is pressed. A split time is the difference between two consecutive laps — the duration of that specific segment. This stopwatch records lap times; subtract consecutive values to get splits.
Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.