Set the time with fields, a quick-entry box such as 1h 30m, or a preset, then get an alarm that keeps ringing until you stop it. It runs in your browser and shares as a link.
Countdown Timer Online
Set the time with fields, a quick-entry box such as 1h 30m, or a preset, then get an alarm that keeps ringing until you stop it. It runs in your browser and shares as a link.
The timer, its label and your sound settings stay in this browser. A share link only encodes the length and label you chose, and nothing is sent to ArrayKit.
The Countdown Timer turns a length of time into a ring that drains until it reaches zero. Enter hours, minutes and seconds, type a duration the way people say it, such as 1h 30m, 25:00 or just 90 for ninety minutes, or tap a preset from one to sixty minutes. Add a label like Tea and it appears on the dial and in the tab title. The finish moment is stored as a clock time rather than counted down tick by tick, so the timer stays right when the tab is hidden. At zero a chosen sound repeats until you press Stop alarm, with Snooze and Restart beside it, or the timer can repeat itself round after round. Everything runs on your device.
Features
Hours, minutes and seconds fields plus a quick-entry box that reads 1h 30m, 25:00, 2m30s or a bare number of minutes
Presets from one to sixty minutes and +1, +5 and +10 minute buttons that also work while the timer runs
A progress ring that drains as time passes, with an optional label on the dial and in the tab title
Alarm, chime or beep that loops until you stop it, with a volume slider and a test button
Snooze, Restart or Repeat when done for round after round on the same length
Optional notification when the tab is in the background, and, where the browser allows it, the screen kept awake while it runs
A share link that carries the length and label and never starts by itself
Full-screen mode for a wall display or a classroom
How to use the Countdown Timer
Type a time in the quick-entry box, fill in the hour, minute and second fields, or tap a preset
Add a label if you want one, then press Start or hit the space bar
Press Pause to hold the time, +1 or +5 minutes to extend it, or Reset to start over
When time is up, press Stop alarm, Restart, or a Snooze button
Example
Input
Quick entry: 1h 30m
Label: Roast
Output
Timer set to 1:30:00 (1 hour 30 minutes)
Share link: https://arraykit.com/countdown-timer?t=5400&label=Roast
The link stores the length in seconds and the label, and opens the same timer ready to start.
Common errors & troubleshooting
Nothing rang when the timer finished. — Browsers allow sound only after you have used the page, so press Start rather than relying on a timer that was never started here. Check that the sound is not set to Off, use Test sound, and make sure the tab and device are not muted.
The alarm started a moment late while I was in another tab. — Browsers slow timers in hidden tabs, so the alarm can arrive a second or more after zero. The remaining time itself is always correct. Keep the timer in its own window if the second matters.
The length is not what I typed. — A bare number means minutes, so 90 is one hour thirty. Write 90s for seconds, or use 1:30 for one minute thirty seconds and 1:30:00 for one hour thirty minutes.
The timer was gone after I refreshed the page. — A running countdown lives only in the open page. The last length, label and sound are remembered, but you need to press Start again. A share link reopens the same timer in one click.
Frequently asked questions
Will the Countdown Timer ring if I switch to another tab?
Yes, as long as the page stays open. Background tabs keep their timers, though the browser may delay them slightly, so the alarm can start a second or so after zero. The tab title shows the time left so you can check from the tab strip, and you can switch on a notification for when the tab is hidden.
How do I set a one hour thirty minute timer quickly?
Type 1h 30m in the quick-entry box and press Enter. The box also reads 1:30:00, 90 for ninety minutes, 5400s, or a mix such as 2m30s, and a bare number is always taken as minutes.
What does a Countdown Timer share link contain?
It holds two things in the address: the length in seconds and the label, for example the page address followed by ?t=5400&label=Roast. Opening it fills in the timer without starting it, and Copy link builds one from whatever is currently set.
Why does the Countdown Timer need a click before it can play sound?
Browsers block pages from playing audio until you have clicked or pressed a key on them, to stop surprise noise. Pressing Start counts, which is why a timer opened from a link waits for you instead of starting on its own.
Does the Countdown Timer keep my screen awake while it runs?
Where the browser allows it, yes: the screen stays on while the timer is running and is released when you pause, reset or leave the page. If the browser refuses the request the timer works normally and the screen may dim.
How long can a Countdown Timer run?
Up to 99 hours, 59 minutes and 59 seconds, which is 359,999 seconds. Longer values typed into a share link are capped to that, and the add buttons stop at the same limit.
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