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Stopwatch

Date & Time

00:00:00.00

Settings

e.g. 5:00 or 90

Space = Start/Pause · L = Lap · R = Reset (disabled while typing in a text field)

About This Tool

Stopwatch – Precise Online Timing With Laps and Splits

Whether you are timing a workout, a cooking step, a presentation rehearsal, or a study session, a reliable stopwatch needs to do one thing perfectly: measure elapsed time without drifting, freezing, or losing your progress. This free online stopwatch starts counting up from zero the moment you press Start, and lets you pause, resume, record laps, and compare your pace against a target — all without leaving the page.

How the Timing Stays Accurate

Instead of counting how many times a repeating timer has fired — an approach that drifts over long durations — this stopwatch measures real elapsed time using the browser's high-resolution clock and recalculates the display from actual timestamps on every update. That means the number you see is always timeNow − timeStarted + previouslyAccumulated, not an accumulation of imprecise ticks. It stays correct even if you switch to another browser tab, minimize the window, or your device momentarily sleeps.

Your session is saved automatically
The running stopwatch, its laps, and your session history are stored in your browser's local storage as you go. If you accidentally refresh or close the tab mid-run, reopening this page restores your in-progress time.

Recording Laps and Splits

Press Lap while the stopwatch is running to capture a split without interrupting the overall timer — useful for tracking laps in a race, rounds in a workout, or stages of a task. Each row in the lap table shows two numbers: the split (time since the previous lap) and the cumulativetime (time since Start). Once you have recorded at least two laps, the fastest and slowest splits are automatically highlighted so you can spot your best and worst segments at a glance. You can also give any lap an optional label, like "Mile 3" or "Set 2," before recording it.

Comparing Against a Target Time

Enter a target duration — for example 5:00 for five minutes, or a plain number of seconds like 90 — and the stopwatch shows live how far ahead of or behind that target your current elapsed time is. This is handy for pacing a timed presentation, staying on schedule during an exam, or checking your progress against a personal best.

Multi-Session Tracking

Every time you press Reset after a run, the elapsed time and lap count are saved to a session history log below the stopwatch. This makes it easy to run several timing sessions back to back — such as multiple sets during a workout — and see the total combined time and the average session length without doing the math yourself.

Display Options and Shortcuts

Choose how much detail the running clock shows using the Display Precision setting — from whole seconds up to millisecond accuracy — and switch between a classic HH:MM:SS clock format or a plain decimal-seconds format. For hands-free control, keyboard shortcuts let you press Space to start, pause, or resume, L to record a lap, and R to reset; shortcuts are automatically ignored while you are typing into a text field so they never interfere with entering a lap label or target time.

Exporting Your Results

Once you have some laps recorded, use Copy Results to copy a plain-text summary of your elapsed time and lap splits to the clipboard, or Download CSV to save the full lap table as a spreadsheet-ready file for further analysis or sharing.

Frequently Asked Questions

Is the Stopwatch free?

Yes, Stopwatch is totally free :)

Can I use the Stopwatch offline?

Yes, you can install the webapp as PWA.

Is it safe to use Stopwatch?

Yes, any data related to Stopwatch only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

How does the online Stopwatch measure time?

The stopwatch uses your browser's high-resolution performance clock rather than a simple countdown of ticks, so it stays accurate to the millisecond and doesn't drift, even during long sessions or when the browser tab is inactive.

What is the difference between a lap and a split?

In this tool, the 'split' is the time since the previous lap, while the 'cumulative' time is the total time since you pressed Start. Both are shown side by side in the lap table so you can compare individual segments and overall progress at once.

Does the stopwatch keep running if I switch tabs or lock my screen?

Yes. Elapsed time is calculated from real timestamps rather than counting timer ticks, so switching tabs, minimizing the window, or letting your device sleep briefly won't cause the displayed time to fall behind — it catches up correctly when you return.

Will my running stopwatch survive a page refresh?

Yes. The current run, its laps, and your session history are saved to your browser's local storage as you go, so accidentally reloading or closing the tab won't lose your progress.

Can I compare my time against a target duration?

Yes. Enter a target time (e.g. 5:00 for five minutes) and the tool shows live how far ahead of or behind that target you currently are, which is useful for pacing workouts, presentations, or timed exercises.

What keyboard shortcuts are available?

Press Space to start, pause, or resume the stopwatch, L to record a lap while it's running, and R to reset. Shortcuts are ignored while you're typing in a text field and can be turned off in the settings.