Calculators & Time
A timer that does not run long
Set minutes and seconds, press start, and get a sound at the end. It stays accurate even if you switch tabs — which is where most browser timers quietly go wrong.
05:00
Presets
The end time is fixed when you press start and compared against the system clock, so a background tab — where browsers throttle timers to once a minute — does not make the timer run long. The alert is a synthesised tone and needs one interaction with the page before browsers will allow it.
- Runs in your browser
- No account required
- Free to use
How it works
Accurate in a background tab
Browsers throttle timers in tabs you are not looking at — often to once a minute — so anything that counts its own ticks loses time. This compares against the system clock on every update, so switching tabs changes nothing about when it finishes.
The end time is fixed at the start
Rather than counting down, the moment it should finish is calculated when you press start and compared against the clock on every update. However irregularly the browser wakes the page, the finish time is unchanged.
The sound is synthesised
A short tone generated by the browser rather than an audio file, so nothing is downloaded. Browsers block audio until you have interacted with the page, which pressing start satisfies.
What it does
Any duration
Minutes and seconds, with presets for the common ones.
Pause and resume
Pausing keeps the remaining time; resuming sets a new end point from that.
A progress bar
So the state is visible at a glance without reading the numbers.
Runs in your browser
No account and no upload — what you type is never sent anywhere. Analytics records that the tool was opened, never what you put into it.
Practical advice
Getting a better result
- The alarm needs one interaction with the page before browsers will allow sound — pressing start is enough.
- Leave the tab open. A closed tab stops running entirely, which no amount of clock-checking can survive.
- For repeated work and break cycles, the pomodoro timer has those built in.
Questions
Things people ask
Does it keep running if I switch tabs?
Yes, and it stays accurate. Browsers throttle background timers heavily — often to once a minute — so a timer counting its own ticks loses time. This one checks the system clock, so it finishes exactly when it should regardless.
Why did the sound not play?
Browsers block audio until you have interacted with the page. Pressing start counts, so the alarm works for any timer you started yourself. Some systems also mute background tabs entirely.
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