Free Stopwatch
NToolHub’s Stopwatch is a precision timing instrument for your browser, accurate to the millisecond. Start, pause, and resume without losing time, record unlimited laps with both split and total times, and review everything in a clean table. Coaches, developers timing code, students, and lab workers all get pro-grade timing with zero setup.
How to Use the Stopwatch
- Click “Start” to begin timing with millisecond precision.
- Pause and resume any time without losing elapsed time.
- Press “Lap” to record split and total times.
- Reset to clear the stopwatch and all laps.
Features
Millisecond display (HH:MM:SS.mmm) driven by the high-resolution performance timer, drift-free pause/resume, unlimited laps with per-lap splits and cumulative totals, a newest-first lap table, and instant reset.
Benefits & Use Cases
Accurate timing improves training intervals, cooking, experiments, and productivity tracking. Because it runs locally with the system high-resolution clock, it stays accurate even if the tab is busy, and there is no app to install.
Tips
Use laps to time segments of a workout or process without stopping the clock. For intervals, pair with the Countdown Timer. Keep the tab visible during critical timing, as background tabs may update less frequently.
Frequently Asked Questions
How accurate is this stopwatch?
It uses the browser’s high-resolution performance timer and updates every 31 milliseconds, giving accuracy well within a tenth of a second for practical purposes.
What is the difference between split and total?
Split is the time since the previous lap, while total is the time since the stopwatch started. Together they show pace and overall elapsed time.
Can I keep timing while switching tabs?
Yes, timing continues in the background. The display may update less often in hidden tabs, but the elapsed time stays correct.
Is there a limit on laps?
No. Record as many laps as you need; the table scrolls and newest laps appear first.
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