It keeps time when you switch tabs
Most timers in a browser count down by ticking once a second. Browsers slow those ticks down in tabs you are not looking at, and stop them altogether when a device sleeps, so the timer runs behind and you find out too late.
This one works the other way round. When you press Start it records the moment it should finish, then reads your clock to see how long is left. Switch tabs for twenty minutes, close the lid, come back: the number is right, because nothing was ever being counted.
What it does
Any duration up to 24 hours
Use a preset or enter hours, minutes, and seconds.
A large, clear display
The countdown and controls sit side by side on larger screens.
An alert at the end
Three rising notes play when the browser lets the page run.
Countdown in the tab
Read the remaining time from the tab strip while the timer runs.
Optional wake lock
The screen stays awake while the timer runs on supported devices.
Test the sound before you rely on it
Browsers only allow a page to make noise after you have interacted with it, which is why the sound is prepared the moment you press Start. If a timer matters, use the test button once and confirm you can hear it. A timer that fails silently is worse than no timer.
How to use it
Pick a duration
Use a preset, or enter the hours, minutes, and seconds you want.
Press Start
Pause and resume at any point; Reset returns to the duration you set.
Keep it visible
Leave the countdown on screen when a room needs to follow the same limit.
Frequently asked questions
Does the timer keep running if I close the tab?
No. Everything runs in the page, so closing the tab ends the timer. The countdown stays correct when you switch away. Browsers may suspend hidden tabs, so the alert can be delayed until the page runs again; keep the timer visible when timing is critical.
Why did I not hear the alert?
Usually because the browser blocked the sound, or the device is muted. Press Start rather than leaving a timer set up but never started, and use the test button to check.
Can I run more than one timer at once?
Yes. Open one timer per tab; each tab keeps its own countdown and displays its own remaining time while it runs.
Is it free?
Yes. There is no account, no limit on how many timers you run, and nothing held back.
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