How accurate is the stopwatch?

Timing is based on the browser's high-resolution performance clock, so elapsed time stays accurate to the millisecond even if the screen refresh is throttled. The display shows minutes, seconds and centiseconds.

What is the difference between a lap time and a split time?

A lap time is the duration of one segment on its own, while the running total (the split) is the elapsed time since you started. This stopwatch shows both for every lap.

What do the up and down marks on laps mean?

When you record more than one lap, the fastest lap is marked with an up triangle and highlighted green, and the slowest is marked with a down triangle, so you can spot your best and worst splits at a glance.

Does the clock keep running if I switch tabs?

Yes. Because elapsed time is measured from the performance clock rather than a per-frame counter, the time stays correct even if the tab is backgrounded and screen updates are paused.

Can I keep timing while recording a lap?

Yes. Pressing Lap records the segment and running total without stopping the clock, so you never lose time between laps.

Are my times saved or uploaded?

No. The stopwatch runs entirely in your browser and keeps your laps only in memory for the current session. Nothing is stored or sent anywhere, and the times are cleared when you reset or leave the page.

Stopwatch with Lap Timer

A simple, accurate online stopwatch with a built-in lap timer. Start, pause, and resume the clock, and tap Lap to record split times for workouts, races, cooking, study sessions, or any task you want to measure.

How it works

Elapsed time is read from the browser’s high-resolution performance clock rather than counted frame by frame, so it stays accurate to the millisecond even when the tab is in the background or the display is throttled. The readout shows minutes, seconds, and centiseconds (hundredths).

Each lap captures two numbers: the lap time (the duration of that segment alone) and the running total (elapsed time since start, also called the split). When you have more than one lap, the fastest is highlighted green with an up triangle and the slowest is marked with a down triangle.

Example

Timing four 400 m laps of a run:

Lap	Lap time	Total
1	01:32.40	01:32.40
2	01:35.10 ▼	03:07.50
3	01:30.80 ▲	04:38.30
4	01:33.00	06:11.30

Lap 3 is flagged as the fastest, lap 2 as the slowest. It is privacy-first: everything runs locally and nothing is stored or uploaded.