PE and field day
Time laps around the track, shuttle runs or relay legs. Fastest and slowest laps are highlighted, so pacing is easy to talk about afterwards.
Classroom Stopwatch
A large online stopwatch for PE, science labs and reading fluency checks: press Start, tap Lap for each split, then copy the times. Free, no sign-up.
Stopwatch
Ready
Lap 1
00:00.00
Lap board
- Laps
- 0
- Average
- –
- Fastest
- –
- Slowest
- –
| Lap | Split | Total | Pace bar |
|---|
Press Space to start or stop · L lap · R reset when stopped · F full screen
Laps stay on this page and are never sent to ChalkSpin.How it works
How to use the classroom stopwatch
- Press StartOr press Space. The big numbers count up in minutes, seconds and hundredths.
- Tap Lap for each splitPress Lap or L each time a runner passes or a group finishes a trial. The pace bar compares this lap with the last one.
- Read the lap boardAverage, fastest and slowest update with every lap, and each row gets a pace bar.
- Copy or show itCopy laps into Google Sheets or Excel, or press F for full screen in the gym or lab.
Ideas for class
Ways teachers use a stopwatch
Counting up is for anything where the time is the result: how long a lap, a trial or a reading takes.
Science labs
Time 10 swings of a pendulum and divide by 10 for a steadier period, or run three trials and use the average on the lap board. A hand-pressed time carries about 0.2 s of reaction time, so repeat trials matter.
Reading fluency checks
Time a cold read, then work out words correct per minute: words read correctly ÷ seconds × 60. A student who reads 112 words correctly in 80 seconds reads 84 WCPM.
Class routines
Time how long lining up or a transition takes today, write it on the board and challenge the class to beat it tomorrow.
Laps explained
Split time and total time
Split is the time for one lap on its own: from the last time you pressed Lap to this one. Total is the time since you pressed Start.
Splits show pacing (did the runner slow down on lap 3?), totals show the finish time. Add up the splits and you always get the total.
| Lap | Split | Total |
|---|---|---|
| 1 | 00:32.10 | 00:32.10 |
| 2 Fastest | 00:30.85 | 01:02.95 |
| 3 Slowest | 00:33.40 | 01:36.35 |
FAQ
Classroom stopwatch questions
How do I record lap times?
Start the stopwatch, then press Lap (or the L key) each time a lap ends. The newest lap appears at the top of the lap board with its split and the total so far. The stopwatch keeps running while you record laps.
What's the difference between split and total?
The split is the time for that lap alone. The total is the time since you pressed Start. Adding every split gives the total.
Can I copy the lap times into a spreadsheet?
Yes. Press Copy laps and paste into Google Sheets or Excel: lap number, split and total land in separate columns, with the fastest and slowest laps marked.
Does the stopwatch keep counting if I switch tabs?
Yes. It measures time from the browser's high-resolution clock rather than counting animation frames, so it stays exact in a background tab and the time shows in the tab title.
How accurate is it?
It shows hundredths of a second and measures to well under a millisecond. In practice the limit is the person pressing the button, about 0.2 seconds, which is the same for any handheld stopwatch.
Can I show it full screen?
Yes. Press Full screen or F. The numbers and the pace bar fill the screen, there are no ads, and Lap and Stop stay available. The screen stays awake while it runs, where your browser allows it. Press Esc to go back.
Keyboard shortcuts
- Space
- Start, stop or resume
- L
- Record a lap
- R
- Reset (when stopped)
- F
- Full screen on or off
- Esc
- Leave full screen
Keep going