Online Stopwatch

What is an online stopwatch?

An online stopwatch is the browser version of the classic click-and-time device: press Start and it counts up from zero in minutes, seconds and centiseconds, press Pause to freeze it, and press Lap to record splits along the way. No app to install, no account to create — the page loads and you're timing within a second. It's the tool you reach for when your phone is across the room, when you want laps in a copyable list, or when you simply need a big, readable clock on a second monitor.

Features

• Centisecond precision — the display shows MM:SS.cs, and the measurement underneath uses the browser's high-resolution clock, so short intervals are captured faithfully.
• True pause and resume — elapsed time is accumulated, not recomputed from the original start, so you can pause as often as you like without losing a single centisecond.
• Lap recording — every lap stores its lap number, the lap time (since the previous lap) and the running total, newest first.
• Keyboard shortcuts — Space starts and pauses, L records a lap, R resets. Keys are faster and more precise than clicking, especially for splits.
• Copy the lap list — one click puts all laps on your clipboard as plain text, ready to paste into a note, spreadsheet or training log.

How to use it

1. Press Start — or just tap the spacebar.
2. Hit Lap (or L) each time a lap, interval or task finishes. The list below fills up with lap and total times.
3. Press Pause (Space again) to freeze the clock; Resume picks up exactly where it stopped.
4. Use Copy laps to grab the whole list, and Reset (or R) to clear everything for the next session.

What people time with it

• Workouts and intervals — time circuits or track repeats and record each round as a lap; the lap column instantly shows whether you're slowing down.
• Swimming and running splits — the lap/total format is exactly how coaches write down splits.
• Cooking and lab work — anything with repeated stages benefits from laps instead of a single total.
• Speedruns, quizzes and games — a big neutral clock everyone can see, with the spacebar as the buzzer.
• Work sessions — time how long tasks actually take; pair it with the Online Timer when you'd rather count down (say, a 25-minute pomodoro) than up.

If you're timing your own reflexes rather than external events, the Reaction Time Test measures the gap between a signal and your click in milliseconds — a fun companion to the stopwatch.

Stopwatch vs. timer

A stopwatch counts up from zero and answers "how long did that take?". A timer counts down from a set duration and answers "tell me when the time is up". If you need an alarm at the end of a fixed period — pomodoro sessions, tea, exams — the countdown timer with its beep is the right tool; for open-ended measurement with splits, you're in the right place.

Private by design

The stopwatch runs entirely in your browser. Nothing is uploaded, no account is needed and no lap data is stored anywhere except your clipboard when you press Copy. Close the tab and it's gone. Browse the full collection of quick utilities on the all tools page.