Multiple Stopwatches
Up to four independent stopwatches on one screen — each with its own name, its own laps and its own Start. For lanes, heats, groups, stations or four things on the stove.
Each stopwatch runs on its own — Start all is for a common gun. Tap a name to rename it. Everything is saved on this device, and Download CSV exports all four side by side. Keyboard: Space start/stop all · R reset all · F full screen.
When four beats one
A single stopwatch answers "how long did that take". Four answer "which of these was quicker", and that is a different question with a different shape: the times only mean something next to each other. Each card here keeps its own laps, so you can take a split on lane 2 without touching lane 3, and the export puts them in one file with the lap numbers lined up.
Swimming and track. One watch per lane or per athlete, named, with splits taken independently.
Classroom stations. One per group, so you can see which station is running long without stopping the others.
Cooking. Four things that went in at different times and come out at different times.
Interviews and debates. One watch per speaker, so total speaking time is a number rather than a guess.
Lab work. Parallel reactions started a minute apart, each with its own elapsed clock.
Timing one thing? The single stopwatch does more per session — fastest and slowest lap highlighting, a +/- column against the previous lap, a shareable image of the results, and a choice of display precision.
What it can't do
These are browser stopwatches, and the limits are the browser's. They keep counting while the page is open, including in a background tab, but a closed tab or a sleeping laptop stops everything — the elapsed time is restored from your device when you come back, not counted through the gap. Displayed precision varies by device.
Good enough for training, a classroom or a kitchen. Not calibrated equipment, and not suitable for official results. What a browser timer actually does, measured rather than described: how accurate is a browser timer?
How many stopwatches can I run at once?
Four. Each one keeps its own name, its own elapsed time and its own laps, and they run completely independently — starting one does not touch the others. If you only need one, the single stopwatch has more per-session tools.
Do they all have to start together?
No, and that is the point — each card has its own Start. There is also a Start all button for a race where everyone goes on the same gun, and pressing it starts every stopped watch at the same instant rather than one after another.
Can I name them?
Yes — tap the name on any card and type. Lane 3, Kettle, Group B, whatever you are actually timing. The names are saved with the session and appear in the exported file.
Are my times saved if I close the tab?
Yes. All four watches, their names and their laps are stored on your device, and a running watch keeps counting while the page is open. Reset all clears everything.
Can I export all four at once?
Yes — Download CSV writes one file containing every watch's laps side by side with the lap number, so you can compare lanes or groups in a spreadsheet without merging four downloads.
Is it accurate enough for a race?
For training, a classroom or a kitchen, comfortably. It is not calibrated timing equipment and is not suitable for official results — displayed precision varies by device, and a background tab updates less often. The measured behaviour is on the browser timing page.
More timing tools
Single stopwatch · Timer (three countdowns at once) · Alarm clock · Using these in a classroom