Stopwatch
Free online stopwatch with millisecond precision, lap recording and total time tracking. Ad-free, mobile-friendly, no install needed.
What Is an Online Stopwatch?
A stopwatch measures elapsed time from a starting moment with millisecond precision. It is used for sports training, cooking, exam timing and lab measurements. The stopwatch on this page runs entirely in your browser, requires no installation and continues counting even if your internet connection drops.
How to Use
Press "Start" to begin counting. While running, press "Lap" to record the current time as a split — the fastest and slowest laps are highlighted automatically. "Stop" pauses, "Resume" continues, and "Reset" returns to zero. You can also use the Spacebar to start and pause from your keyboard.
Common Use Cases
Time running splits during training, measure sets in football or basketball drills, track multiple cooking steps in the kitchen, pace a thesis presentation, monitor your child's homework time, or record laboratory reactions. The lap function lets you see the duration of each segment within a single session.
Tips
If you close the tab the stopwatch will stop — pin the tab during long sessions. On mobile, set screen-lock timeout to "Never" so the count keeps running. You can open the stopwatch in multiple browser tabs at once for parallel timings. Take a screenshot before resetting if you want to keep your lap history.
Frequently Asked Questions
How do I record a lap time?
Press the "Lap" button while the stopwatch is running. Each press adds the current time as a split. The fastest and slowest laps are highlighted automatically.
Does the stopwatch stop if I close the tab?
Yes — closing or refreshing the tab resets the stopwatch. For long sessions, keep the tab open and avoid refreshing.
How accurate is the stopwatch?
The stopwatch uses the browser high-resolution time API, giving millisecond precision. Drift stays below 10 ms depending on device performance.
Are there keyboard shortcuts?
Yes — the Spacebar acts as start/pause. On mobile devices the on-screen buttons perform the same actions.
Can anyone else see my stopwatch data?
No. All counts and lap records are kept only in your browser. They are never sent to a server and are cleared when the page closes.