Stopwatch with Laps
A precise online stopwatch with laps, timed to the hundredth of a second.
- No laps yet. Press Lap while the timer runs.
This stopwatch runs entirely in your browser. Nothing is uploaded or saved anywhere.
How to use this tool
Press Start to begin timing. The display updates live to hundredths of a second. While it runs, press Lap to record a split without stopping the clock, building a full lap log as you go. Press Start again (it now reads Stop) to pause, and press it once more to resume from where you left off. Reset clears the time and the lap list so you can start fresh. Use Copy laps or Download laps to save your lap log tracker as plain text.
How the timing works
This web stopwatch uses performance.now(), a high-resolution clock measured in milliseconds, instead of the wall clock. Each frame it adds the time since the last Start mark to any time accumulated before a pause. That keeps the millisecond timer accurate even if the browser briefly skips a frame, because the elapsed value is always recomputed from real timestamps rather than counted up tick by tick. The screen refreshes with requestAnimationFrame so it stays smooth and easy on the battery.
A real example
Say you are timing four laps of a track. You press Start and run. At 1:02.45 you press Lap, then again at 2:05.10, 3:09.80, and 4:11.30. The lap log shows split times of 1:02.45, 1:02.65, 1:04.70, and 1:01.50. The fastest lap (1:01.50) is highlighted in green and the slowest (1:04.70) in red, so you can spot your strongest and weakest segments at a glance.
Common questions
How precise is this stopwatch?
It displays time to the hundredth of a second (two decimals) and tracks the underlying value in milliseconds using the browser high-resolution clock. It is well suited for everyday timing, sports splits, cooking, and study sessions, though it is not a certified instrument for official competition.
What does the Lap button do?
Lap records the current total time as a split and keeps the clock running. Each entry also shows the time for that individual lap, so you get both the cumulative time and the per-lap duration in one lap log tracker.
Does the timer keep running if I switch tabs?
Yes. Because the elapsed time is calculated from real timestamps rather than a frame counter, the total stays correct even if the tab is in the background and the on-screen updates pause. When you return, the display catches up to the true elapsed time.
Are my lap times saved or sent anywhere?
No. Everything happens locally in your browser. Nothing is uploaded to a server, and your laps disappear when you reset or close the page. Use Copy or Download if you want to keep them.
Why use a stopwatch online with laps instead of an app?
There is nothing to install and it works on any device with a browser. Open the page, start timing, and record laps instantly. It is a simple, free web stopwatch that loads fast and respects your privacy.