Stopwatch & Timer
A precise stopwatch with laps and a countdown timer with an alarm, right in your browser.
Laps 0
| Lap | Lap time | Total |
|---|
How to use the stopwatch and timer
- Stopwatch: press Start or the Space key. Time is shown in minutes, seconds and hundredths of a second.
- Press Lap to record a split without stopping the clock. The fastest and slowest laps are highlighted in the list.
- Press Pause to stop and Resume to carry on. Reset sets the time back to zero and clears the laps.
- Timer: open the Timer tab, type the hours, minutes and seconds and press Start, or tap a quick time such as 5 min to start straight away.
- When the time is up, an alarm sounds for up to 30 seconds and the tab title flashes. Press Stop alarm or Esc to silence it.
A stopwatch and timer you can trust
Whether you are timing a run, a presentation, a plank or the pasta on the stove, you need a clock that starts with one tap and doesn’t drift. This page gives you both: a stopwatch that counts up with lap times, and a countdown timer that rings when the time is over. Each one runs on its own, so you can time a workout with the stopwatch while the timer counts down your rest.
Why it stays accurate
Many online timers count by adding a little time every second. Browsers slow those updates down in background tabs, so the timer falls behind. This tool works differently: it notes the exact moment you pressed Start and, every time the screen is drawn, it calculates the time from your device’s clock. Switch tabs, open another app or come back an hour later, and the time is still right. Even if you refresh or close the page, the stopwatch and timer pick up where they were, because their state is saved in your browser.
Lap times
Each press of Lap saves a split. The list shows the time of each lap and the total time at that point, with the newest lap on top and the lap in progress updating live. With two or more laps, the fastest lap is marked in green and the slowest in red, which makes it easy to compare running laps, swimming lengths or rounds of an exercise. Copy puts the whole table on your clipboard, ready to paste into a spreadsheet.
Countdown timer and alarm
Set any time up to 99 hours, 59 minutes and 59 seconds, or pick a quick time: 25 minutes is the classic Pomodoro focus session, 3 minutes is about right for a soft-boiled egg. While the timer runs you see when it will end, the ring empties as time passes and +1 min adds extra time without stopping. The alarm is scheduled with your browser’s audio system the moment you press Start, so it rings on time even when the tab is in the background. The remaining time is also shown in the tab title.
Full screen and shortcuts
Press Full screen or F to show a large clock that can be read from across a room, ideal for classrooms, meetings and exams. On a computer, Space starts and pauses, L records a lap and R resets. While the clock is running, supported browsers keep your screen from going dark.
Everything runs in your browser. Nothing is sent to a server, there is no sign-up, and the only thing stored is the timer state on your own device.
Frequently asked questions
Does it keep running if I switch tabs or close the page?
Yes. Time is calculated from your device’s clock rather than counted tick by tick, so switching tabs doesn’t slow it down. If you refresh or close the page, the stopwatch and timer continue from the right time when you open it again. The alarm can only sound while the page is open, though.
Will the alarm ring if my phone screen is off?
It depends on the phone. Many phones pause the browser when the screen locks, so the alarm may only sound when you return. While the timer runs, this page asks the browser to keep the screen on; for important alarms, keep the page open and the screen unlocked.
Why can’t I hear the alarm?
Check that “Alarm sound” is ticked, that your device isn’t muted and that the volume is up. On iPhone the ring/silent switch also mutes sound in web pages. The tab title still flashes and phones that support it vibrate.
How accurate is the stopwatch?
The stopwatch shows hundredths of a second and is as accurate as your device’s clock. When you time by hand, your reaction time (usually 0.1–0.3 seconds) matters far more than the clock itself.
Can I save or copy my lap times?
Laps are kept in your browser until you press Reset. Press “Copy” above the lap list to copy them as a table you can paste into Excel, Google Sheets or a note.