Developer
Countdown Timer
Set a time, start it, and hear about it when the time is up — even from another tab.
Ready — 5 minutes set.
A countdown is mostly a display problem. You set a duration, and then you want to know how much of it is left without sitting and watching the tab. This one puts the remaining time in the tab title, so the timer can sit pinned in the background while you work and still be readable at a glance.
The count is worked out from a deadline — the wall-clock moment it should reach zero — rather than by subtracting a tick at a time, so a browser throttling a hidden tab or a laptop sleeping for a minute cannot make it drift. The alert is an oscillator built with the Web Audio API, which means no sound file to download and no dependency on being online.
How to use it
- Set hours, minutes and seconds, or press a preset for one, five, ten, twenty-five or sixty minutes.
- Press Start. The digits count down and the tab title shows the time left.
- Press Pause to hold it where it is, Resume to carry on, or Reset to go back to the duration you set.
- Leave the beep box ticked for three tones at zero, or untick it for a silent countdown.
Questions
Will the alarm still sound if I am in another tab?
The countdown reaches zero on time either way, and the tones are played when it does. Browsers do allow a page to play audio from a background tab once you have interacted with it, which pressing Start counts as. A hidden tab's timers can be delayed by up to about a second, so the beep may arrive a fraction late; the time shown when you come back is always right.
Why was there no sound the first time I tried it?
Browsers block audio until a page has been clicked, so the sound is created on your first press of Start. If the box is ticked and you still hear nothing, check the tab is not muted and the system volume is up — nothing else on the page can silence it.
Does it keep counting while my laptop is asleep?
It counts towards a real deadline in time, not towards a number of ticks, so when the machine wakes it shows the true remaining time — which is usually zero. There is no sound while a machine is suspended, because there is nothing running to play it.
How do the presets work?
Each one fills in the hours, minutes and seconds fields and clears any running countdown. After a preset you can still change a field to fine-tune it before pressing Start.