Stopwatch

📖 Tool Introduction

Stopwatch is a completely free, instant-use online precision timer built on top of the browser's high-resolution clock, accurate to one hundredth of a second (ten milliseconds). Whether you are timing laps on a run, cooking on the stove, pacing exam questions, keeping a speaker within a meeting slot, tracking lab steps, or measuring how long your kid spends on a set of exercises, this stopwatch handles the job. Compared with the stopwatch app on your phone, the big advantage here is that you open a web page and start immediately: no unlocking, no app launch, just one click on your desktop. The centre of the screen is a huge monospaced readout: minutes and seconds in large digits, centiseconds in a smaller tone beside them, so the time is legible even from across a room. Once started, the digits refresh every ten milliseconds for a smooth, flicker-free display. The Lap button captures split times for multi-round activities such as running laps, swimming sets or gym circuits, recording both the per-lap time and the cumulative total; the newest lap sits on top of the list so you can instantly compare your fastest and slowest rounds. You can pause and resume seamlessly, or reset everything to zero in one click. The whole tool runs entirely in your browser, sends no network request, requires no account and no installation, and ships in three languages with a dark theme that keeps the numbers sharp and easy on the eyes during long timing sessions. Because every calculation happens inside your own browser tab, you never have to worry about lap data being uploaded or tracked, which makes the tool feel genuinely private and dependable for sensitive workouts, cooking steps or exam practices.

✨ Key Features

• Centisecond precision: driven by performance.now() and shown to 0.01 second accuracy
• Start / Pause / Resume: one click toggles state; pause freezes the clock, resume continues seamlessly
• Lap recording: each lap stores its split time and cumulative total, newest on top
• One-click reset: zeroes the timer and clears all laps to start a fresh round
• Huge monospaced digits: centiseconds in smaller type, readable from across the room
• Fully offline: no network required, timing stays accurate even with no signal

📝 How to Use

1. Click Start and the stopwatch begins at 00:00.00
2. When you want to mark a lap, click Lap; that split appears in the list below
3. Click Pause to freeze the clock midway; click Start again to resume
4. When a session is done, click Reset to zero everything for the next round
5. The lap list shows each split and the cumulative total up to that point

⚠️ Notes

• Timing accuracy: driven by performance.now() with 10ms refresh; background tabs may be throttled by the browser
• Lap rule: split = current total minus previous lap total; newest lap sits at the top of the list
• Reset warning: reset clears all lap records, so confirm before pressing it
• Hours display: beyond 60 minutes the format switches to hh:mm:ss while centiseconds are preserved
• Privacy first: the tool runs fully offline and stores nothing, so your timing data never leaves the device