Countdown Timer
Count down any time, from seconds to 100 hours, with an alarm, an optional notification and the time left in the tab title. Keeps time in a background tab.
Countdown
5 min
05:00
Set the time
The time is kept from the clock, so it stays right in a background tab, on a sleeping laptop or after a reload. Keep the page open for the alarm to sound.
How is this calculated?
End time = when it was started + time left at that moment. Time left = duration − time elapsed.Runs in your browser — nothing you enter leaves this device.
About this tool
What it does
Countdown Timer counts down any length of time, from a few seconds to 100 hours, and sounds an alarm when it reaches zero. Press a quick time — 1, 3, 5, 10, 15, 20, 30, 45 or 60 minutes — or type your own in whatever form comes naturally: 25 for 25 minutes, 2:30, 1:00:00, or 1h 30m. Give it a label such as “Tea” or “Exam” and the label appears with the time. While it runs, the time left is shown large, as a bar, and in the tab title, so you can read it from another tab. The alarm is three short beeps made by the browser, and you can also allow a notification so it reaches you when the page is not in view. Because the timer works out the end time from the clock rather than counting seconds, it stays right in a background tab or on a laptop that sleeps, and a reload picks up where it was.
How to use it
- Press a quick time, or type one and press Set.
- Add a label if you like.
- Press Start. Pause and Resume as needed; Reset goes back to the full time.
- Optionally allow notifications. When time is up, press Again to repeat it.
Limits and your data
- The page must stay open for the alarm to sound; a closed tab cannot ring. A phone may delay or silence alarms while the screen is locked to save battery.
- Browsers only play sound after you have clicked on the page, so the alarm works once you have pressed Start yourself.
- Notifications need your permission, and your system’s Do Not Disturb or Focus mode can hold them back.
- For repeated work and rest periods, use the Pomodoro or interval timer.
- The timer runs in your browser. Its settings and the running time are kept on this device only.
Questions
Will the timer work if I switch to another tab?
Yes. It knows when it will end, so it stays accurate in the background and the alarm is scheduled for that moment. Keep the tab open.
How do I set a timer for 1 hour 30 minutes?
Type 1:30:00 or 1h 30m and press Set. A plain number such as 90 is read as minutes.
Why is there no sound?
Check the device volume and that the tab is not muted. Browsers block sound until you interact with a page; pressing Start counts.
Can it notify me?
Press “Also notify me when time is up” and allow notifications when asked. The alarm and the on-page message work either way.