Stopwatch
Precision stopwatch with start, stop, lap recording, and reset functionality. Lap times are displayed in a table for easy comparison. Input never leaves your device — everything runs locally in your browser.
How to Use the Stopwatch
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Frequently Asked Questions
How precise is it?
Whole-second display ticking once per second in HH:MM:SS — plenty for training splits and casual timing. Not millisecond precision and not certified for official race timing.
How do laps work?
Hit Lap anytime: the lap time records into the on-screen table with the running total. There is no export or copy button — read totals off the table.
Does it run in the background?
It ticks once per second while the tab stays active; background throttling can slow the count since it increments per tick rather than from the wall clock. Keep the tab foreground for accurate runs.
Stopwatch vs timer — which do I need?
Stopwatch counts up from zero (measuring how long something took); timer counts down to zero (alerting when time is up). This page is the former.
When using Stopwatch, is anything uploaded?
No. Everything runs locally in your browser. Nothing leaves your device.
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Last updated October 2026