Online stopwatch

An online stopwatch that shows hundredths

This online stopwatch starts at zero and counts up. The time appears in large digits as minutes, seconds and hundredths: 02:42.60 means 2 minutes, 42 seconds and 60 hundredths. Past 59 minutes the hours are added in front, as in 1:00:00.00. It runs in your browser on a computer, tablet or phone, with nothing to install and no account.

Use it to time a run, lengths in the pool, interval training or laps of a track. It is just as handy away from sport: checking how long a recipe step really takes, rehearsing a talk, timing a round of a board game, running a science experiment in class, or measuring how long a task takes you.

How to use the stopwatch

1. Click "Start" or press the space bar. The same button turns into "Pause", then "Resume", and the time carries on from where it stopped.
2. Click "Lap" (or press L or Enter) each time a lap ends. A row is added to the "Lap times" table with the lap number, the lap time and the total. The latest lap is at the top. The button only works while the stopwatch is running.
3. Once there are three laps, the fastest and the slowest are marked with a colour and a label.
4. "Full screen" enlarges the digits so they can be read from a distance.
5. "Copy laps" puts the table on the clipboard as tab-separated text, in lap order, ready to paste into a spreadsheet.
6. "Reset" clears the time and every lap straight away, without asking for confirmation.

While the stopwatch is running, the time also shows in the browser tab title, to the nearest second.

Split time and lap time: how to read the table

The "Total" column is the split time: the time since the start when you pressed the button. The "Lap" column is the lap time: the time since the previous press. Here is a 200 metre swim in a 50 metre pool, with one press per length:

The swimmer finishes in 2 minutes 42.60 seconds. The first length is the fastest (00:38.20) and the third the slowest (00:42.35). Remember to press "Lap" at the finish and then "Pause": otherwise the last lap is not written to the table.

How accurate is it?

The display goes down to hundredths of a second, and the time is worked out from your device's clock, not counted frame by frame, so it does not drift. The weak link is the person pressing the button. Human reaction time is about 0.2 seconds, at the start and again at the finish. That is fine for training, lessons and games, but a hand-operated stopwatch cannot separate two runners by a hundredth. That takes electronic timing.

Stopwatch or timer?

A stopwatch counts up and answers "how long did that take?". A timer starts from a set duration, counts down to zero and sounds an alarm. For a four-minute pot of tea, use the timer on this site.

Frequently asked questions

Does the stopwatch keep going if I switch tabs?

Yes. The time is recalculated from the moment you started, so it stays correct when the tab is in the background or your phone screen turns off.

What happens if I reload the page?

Nothing is lost. The start time and the laps are kept in your browser, on your device, so a running stopwatch picks up with the right time after a reload. In a private window, that memory is cleared when you close the window.

How many laps can I record?

Up to 999 laps per session. After that, the "Lap" button is switched off.

Why is no lap highlighted?

You need at least three laps. If every lap has exactly the same time, none is marked.