Stopwatch | How to use and interpret results
Accumulate elapsed time and record lap-button moments. Each lap is a cumulative timestamp since the start, rather than the duration since the previous lap.
- Runs in your browser
- Nothing is uploaded
- No signup; device limits apply
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How to use this tool
Use start and stop to control accumulation and press lap at each moment to record. Restart continues from the accumulated value; reset clears the session's readings.
Results and examples
A lap at ten seconds and another at fifteen seconds produce 10 and 15. The second interval is a separate subtraction, 15−10=5 seconds.
Worked example
A lap at ten seconds and another at fifteen seconds produce 10 and 15. The second interval is a separate subtraction, 15−10=5 seconds.
Limitations
- Device-clock changes and browser delays affect timing.
- Official event timing and persistence after closing the tab are not guaranteed.
Fields
| Field | Guidance and constraints |
|---|---|
| Lap times | Check the unit and format displayed beside this field. |
Data handling
Processing stays in the current browser tab; the site does not upload tool input for the calculation itself.
Sources
Frequently asked questions
Is the second 15-second lap an interval?
A lap at ten seconds and another at fifteen seconds produce 10 and 15. The second interval is a separate subtraction, 15−10=5 seconds.
Can I use this as official event timing?
Device-clock changes and browser delays affect timing. Official event timing and persistence after closing the tab are not guaranteed.
