Stopwatch & Timer

Key features

• Stopwatch measuring to a hundredth of a second, driven by the browser's high-resolution clock.
• Unlimited laps with per-lap splits and running totals — the fastest lap is highlighted green, the slowest rose.
• Pause, resume and reset without losing the lap list.
• Countdown tab with a draining progress ring, from one second up to three hours.
• Triple beep, screen flash and a toast when the countdown hits zero.
• Both modes stay mounted — switch tabs mid-run without stopping either timer.

How it works

1. 1

   Start the stopwatch

   Hit Start in the Stopwatch tab. The display ticks in MM:SS.CS format and the button becomes Pause.

2. 2

   Record laps

   Press Lap whenever you want a split. Each entry shows that lap's time plus the running total, with best and worst laps colored automatically.

3. 3

   Pause or reset

   Pause freezes the clock and turns into Resume. Reset wipes the time and all laps for a fresh run.

4. 4

   Set a countdown

   Switch to the Countdown tab, enter minutes (0–180) and seconds (0–59), then Start. The ring drains as time passes.

5. 5

   React at zero

   A triple beep plays, the panel flashes red, and a Time's up! toast appears. Pause and resume work here too.

Tips for better results

• 💡Switching between the Stopwatch and Countdown tabs never stops either timer — both keep running in the background.
• 💡Editing the countdown duration while it's idle resets it; while it's running the inputs lock, so you can't break a live timer by typing.
• 💡The countdown is deadline-based, so the remaining time stays accurate even if the tab gets busy — though browsers may delay the beep in heavily throttled background tabs.
• 💡Use the green/rose lap coloring to spot pacing problems at a glance in workouts or experiments.
• 💡Lap history isn't saved between resets — note or screenshot anything you need to keep.

Frequently asked questions