Stopwatch
What Is a Stopwatch?
A stopwatch is a timekeeping device used to measure elapsed time from a specific starting point. Unlike a clock that shows the current time of day, a stopwatch counts upward from zero, allowing you to precisely measure the duration of an activity. This online stopwatch provides centisecond (1/100th of a second) precision and includes lap timing, making it suitable for a wide range of timing needs without requiring a physical device.
How to Use
Click Start to begin the stopwatch. Use Lap to record split times without stopping. Click Stop to pause, and Reset to clear everything. You can resume timing after stopping by clicking Start again.
Common Use Cases
- Sports and fitness — time runs, laps, intervals, and workout sets
- Cooking — track boiling, steeping, or baking durations
- Productivity — measure how long tasks take using time-boxing techniques
- Education — time exams, presentations, or science experiments
- Games — set time challenges or measure reaction times
Features
- Centisecond precision (1/100th of a second)
- Lap time recording with split display
- Pause and resume without losing elapsed time
- Clean, distraction-free interface
- Works entirely in the browser — no installation required
Privacy
All processing happens in your browser. No data is sent to any server.
FAQ
What is the difference between a stopwatch and a timer?
A stopwatch counts upward from zero to measure elapsed time, while a timer counts down from a set duration to zero. This tool is a stopwatch for measuring elapsed time and does not offer a countdown.
What does the lap feature do?
Lap records the current elapsed time (a split) without stopping the clock. Each press adds an entry to the list, letting you compare times across running laps or intervals.
Is it okay to switch tabs or leave the page while timing?
The stopwatch runs within the browser page. Switching tabs keeps it running, but reloading or closing the page resets it, so keep the page open while timing.
Is the recorded time sent to a server?
No. Everything — start, stop, lap, and reset — happens in your browser, and your timing data is never sent to or stored on any server.
How precise is the timing?
It displays centiseconds (1/100th of a second), which is plenty for everyday use. Browser timers are not certified instruments, though, so they are not suited to applications needing millisecond-level competitive precision.