Online timer and stopwatch
05:00
The alarm rings even when the tab is in the background: keep your device's sound on and the page open.
Tip: the space bar starts and pauses.
How to use this calculator?
1. Pick a quick duration or enter a custom one in hours, minutes and seconds
2. The timer starts: pause, resume or reset it at any time
3. When it ends, an alarm rings and the tab title tells you
4. Switch to the Stopwatch tab to time something to the hundredth and record laps
Quick answer
How do you set an online timer?
Click a quick duration (for example 5 min): the timer starts straight away and rings at 00:00. For a precise duration, enter hours, minutes and seconds, then start it: 1 h 30 is set with 1 hour and 30 minutes, which is 5,400 seconds. The space bar pauses and resumes.
| Use | Suggested duration |
|---|---|
| Soft-boiled egg | 3 min |
| Pasta | 10 min |
| Pomodoro session | 25 min |
| Pomodoro break | 5 min |
| Power nap | 20 min |
About the Online Timer and Stopwatch
What is it?
Two tools in one: a timer that counts down a duration and rings an alarm at the end, and a stopwatch that measures elapsed time to the hundredth of a second, with laps. Everything runs in your browser, with nothing to install.
Why use it?
A timer helps in the kitchen, for workouts, revision, the Pomodoro technique (25 minutes of work) or to limit children's screen time. The stopwatch measures a lap, a presentation or an exercise, and compares laps with each other.
How does it work?
Time is not counted second by second: the tool stores the exact end time (or start time for the stopwatch) and computes the difference with the device clock on every refresh. It therefore stays accurate even when the tab is in the background and the browser slows the page down. The alarm is a sound generated by the browser, repeated for 30 seconds.
Usage tips
- The space bar starts and pauses, handy when your hands are busy
- The tab title shows the remaining time, so you can see it from another tab
- Put the timer in full screen to show it in a classroom or a meeting
- A link to the page keeps the chosen duration: bookmark it to get your 25 minute timer back
- On mobile, keep the screen on: a phone in sleep mode can mute the page