⏰ Online Alarm Clock
Quick answer
An online alarm clock runs in your browser and plays a sound at a time you choose. Add one or more alarms with labels, such as “Wake up” or “Meeting”, and the clock checks the current time every second. The page and tab must stay open, because closing them stops the alarm from ringing.
Current local time
Monday, 26 October 2026
No alarms set yet. Add your first alarm above.
Browser alarms only ring while this tab remains open. Do not close the tab or shut down the device before the alarm time.
✅ 100% free · 🔒 Runs in your browser — files never leave your device · 🚫 No sign-up
How to use the Online Alarm Clock
- Check that the large clock shows your correct local time.
- Pick an alarm time and type a short label.
- Press Add alarm and confirm that it appears in the list.
- Leave this page open; when the time arrives, press Stop alarm to silence the sound.
Frequently asked questions
Will the online alarm ring if I close the page?
No. The page must stay open in your browser for the alarm to ring. Closing the tab, browser or device will prevent it, so keep the page open and your sound turned on.
Can I set more than one alarm?
Yes. Add as many alarms as you need, each with its own time and label. Delete an alarm at any time from the list.
How long does the alarm sound last?
When an alarm triggers, the sound repeats every two seconds for about 30 seconds unless you press Stop alarm sooner.