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Online Alarm Clock

Set wall-clock alarms that ring right in your browser tab, with snooze and a live clock.

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Keep this tab open — alarms only ring while the page is open and your device is awake.

About this tool

An online alarm clock is a browser page that watches the wall-clock time and rings when the moment you chose arrives — no app to install and nothing to sign up for. Pick a time, optionally give the alarm a label, and add as many alarms as you need; the big live clock and a next-alarm countdown show exactly when the next one will fire.

When an alarm goes off, the page plays a repeating beep synthesized on the spot with your browser's Web Audio engine and flashes the tab title so you notice it even from another tab. You can dismiss the alarm or snooze it for 5 or 10 minutes with one click.

Everything runs entirely in your browser: the alarms live in the open page and no data is sent anywhere. The one rule to remember is that the tab must stay open (and your device awake, with sound on) for the alarm to ring — use the test-sound button once to confirm audio is working before you rely on it.

Frequently asked questions

Will the alarm ring if I close the tab?
No. The alarm runs inside the page, so the tab must stay open and your device must be awake with the volume up. It still rings if the tab is in the background — the tab title also flashes so you can spot it.
Why should I press the test-sound button first?
Browsers only allow sound after you have interacted with the page. Adding an alarm or pressing test sound unlocks audio, and the test also confirms your speakers and volume are working.
Can I set more than one alarm?
Yes. Add as many alarms as you like — they are listed in time order, each can carry its own label, and you can remove any of them individually.
What happens if I set a time that has already passed today?
The alarm is automatically scheduled for that time tomorrow. The confirmation toast and the alarm list show the exact time it will ring.

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