Online Stopwatch
Start, stop and record laps. Time shows to a hundredth of a second.
Keys: Space starts or pauses, R resets, F toggles fullscreen.
How to use it
- Press Start to begin timing.
- Press Lap to record a split without stopping the clock. The lap list shows each split and the running total.
- Press Stop to pause and Resume to carry on. Reset clears everything.
What people use it for
- Running, swimming and cycling laps
- Timing how long a task really takes
- Science experiments and reaction times
- Speaking and presentation practice
- Games and challenges with friends
Lap times help you see pace. If your laps get slower over the session, start the next one a little easier.
Questions
What is the difference between a lap and a split?
Here each row shows the lap (time since the previous lap) and the total time since you pressed Start.
How precise is it?
It shows hundredths of a second using the browser's high-resolution clock. For sport, the limit is how fast you press the button.
Does the timer keep working in another tab?
Yes. It measures real clock time, so it stays correct while you use another tab or app. The time left also shows in the tab title. Your browser may mute sound in a background tab on some phones, so keep the screen on for the alarm.
Is it free?
Yes. No sign-up, no install and no limit. Everything runs in your browser and nothing is sent or stored.
Does it work on a phone?
Yes. It works in any modern phone browser. While a countdown is running we ask the screen to stay awake where your browser allows it.