Online Stopwatch
Precise stopwatch with lap times and millisecond display. Free, no signup required.
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How to Use the Online Stopwatch
- 1
Start Timing
Click the Start button to begin the stopwatch. The display updates every 30ms for smooth millisecond precision.
- 2
Record Laps
Click Lap while the stopwatch is running to record a split time. Each lap shows the total elapsed time and the split (time since last lap).
- 3
Pause and Resume
Click Pause to stop the display at the current time. Click Resume to continue from where you left off.
- 4
Reset
Click Reset to clear the display and all lap times back to zero.
About the Online Stopwatch
An online stopwatch is an essential timing tool for athletes, students, teachers, coaches, and anyone who needs to measure elapsed time with precision. Unlike a simple phone stopwatch, a browser-based stopwatch is always accessible — just open the URL and start timing immediately.
UseToolify's stopwatch measures time with millisecond precision using Date.now() under the hood, updating the display every 30 milliseconds for a smooth, real-time feel. The display shows hours (when needed), minutes, seconds, and centiseconds in a large, easy-to-read font.
The lap feature lets you record split times without stopping the main clock. Each lap entry shows both the split time (time since the previous lap) and the total elapsed time — perfect for running, cycling, swim practice, or any multi-segment event. Laps are shown newest-first for easy reference.
Common uses include: athletic training (lap swimming, 400m splits), classroom quizzes (timed questions), cooking (tracking multiple dishes), games (speed-run timing), and productivity (tracking task time). The stopwatch runs entirely in your browser with no server calls once loaded.
The pause and resume functionality means you can stop the clock for breaks and continue without losing your progress. All data is kept in memory — refreshing the page resets the clock.
You may also find our Countdown Timer and Interval Timer helpful.
How to Use
- 1. Press Start to begin timing.
- 2. Press Lap to record a split without stopping the clock.
- 3. Use Pause to hold, and Reset to clear the time and all laps.
Frequently Asked Questions
How accurate is this stopwatch? expand_more
The stopwatch uses Date.now() which is accurate to within a few milliseconds in modern browsers. The visual update rate is ~30ms for smooth animation.
How many laps can I record? expand_more
There is no limit to the number of laps. However, lap times are stored in memory and will be cleared on page refresh.
Does it work on mobile devices? expand_more
Yes, the stopwatch works on all modern mobile browsers. The large tap targets make it easy to use on touch screens.
Can I save or export my lap times? expand_more
Currently you can copy the displayed laps manually. An export feature may be added in a future update.
What does the split time mean? expand_more
The split time shows how long each individual lap took — the time between the previous lap and the current one.