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Laps
A free online stopwatch that measures to the hundredth of a second, records lap and split times, and marks your fastest and slowest lap. It keeps time from the system clock, so it stays correct in a background tab or after a reload, and runs full screen for a gym, track or classroom.
How to use
- Press Start. The time counts up to the hundredth of a second.
- Press Lap (the flag) to record a lap; the fastest lap is marked green and the slowest red.
- Press Pause to stop, then Reset to clear. Copy all laps as plain text from the lap list.
- The stopwatch reads the system clock, so it stays exact in a background tab and keeps running after a reload.
- Laps and the running time are kept in this browser only.
Laps and splits
Press Lap (or L) each time a runner passes, a set ends or a speaker changes. Every row shows the lap time and the total elapsed time, which is the split. The fastest lap turns green and the slowest red, so uneven pacing stands out at a glance.
Copy all turns the list into plain text you can paste into a spreadsheet or a message, one lap per line.
How accurate is it?
The stopwatch reads the device clock when you press Start and when you look again, so timing does not drift even if the browser slows a hidden tab. What limits precision is human reaction time: a hand press is typically off by around 0.1 to 0.2 seconds, so the hundredths are best used to compare laps timed the same way.
Stopwatch or timer?
A stopwatch counts up from zero and tells you how long something took; a timer counts down from a set time and alerts you when it ends. Switch between them with the tabs above the digits.
Frequently asked questions
Does the stopwatch keep running in the background?
Yes. It is based on the system clock, so it keeps counting while you use other tabs and even after you reload the page.
How do I record a lap?
Press Lap or the L key while the stopwatch runs. Each lap shows its own time and the total so far.
What do the green and red laps mean?
Green marks your fastest lap and red your slowest, once you have at least two laps.
Can I export my lap times?
Press Copy all to copy every lap as plain text, ready to paste into a spreadsheet, notes or chat.
What does the stopwatch show after an hour?
It keeps counting in hours, minutes and seconds with hundredths, so long sessions are timed without resetting.