Stopwatch tools · Laps & training
Lap Stopwatch
Every lap tells a little more of the story.
Ready when you are
Current lap · 00:00.00
Ready when you are.
Reset this session and remove its recorded marks? Export first if you want to keep them.
Your results
Completed marks appear here. Add a note to remember the details.
A fresh start. Your first mark goes here.
How to use the lap stopwatch
Start once, then record a lap at each boundary. The main clock keeps the total active time; the smaller clock shows the current, unfinished lap. Add a note beside any recorded lap and undo the latest mark if you tapped too early.
Statistics use completed laps only. Pausing excludes the break from both lap and total time. The average adds all completed lap times and divides by their count; the median is the middle value after sorting. Fastest and slowest labels identify extremes without relying on color.
What is the difference between a lap and a split?
A lap is the interval since the previous mark. A split is the total since the start, excluding pauses. Two 45-second laps produce splits of 45 seconds and 1 minute 30 seconds. CSV includes both formatted times and numeric seconds.
How accurate is the stopwatch?
The display can show hundredths of a second, but human reaction and browser input latency affect a manual measurement. Live timing uses a monotonic clock, so changing the device time does not change an open session. After a refresh, recovery uses saved device timestamps. Device sleep and a changed clock can affect that recovery. Keep this page and device awake for dependable timing.
Where are my results saved?
Only in this browser on this device, with no account required. Use one tab per tool to avoid overwriting the same saved session. Export CSV before clearing local settings. Each session can hold up to 500 marks and seven days of active elapsed time. Live updates stop while paused; no stopwatch readings are sent to our server.