Online Alarm Clock
Set several labeled alarms in one clean tab and keep them saved on this device.
- Fewer clicks, keyboard friendly
- Features others lock behind paywalls
Current local time
Quick set
Your alarms
No alarms yet. Add one for a meeting, break or reminder.
Keep this tab open and test the sound before relying on an alarm. A browser cannot ring while the device is asleep or shut down.
How to use
- Choose an alarm time and optionally write a label.
- Press Test sound, then select Add alarm.
- Leave this tab open while you work in other tabs.
- Use the Enabled switch to pause an alarm, or Remove to delete it.
- When an alarm rings, press Dismiss alarms or Esc to stop the sound.
Why the alarm checks the real clock
Browsers intentionally slow background tabs to save battery. Counting one-second timer ticks can therefore make an alert late after the tab has been in the background. This alarm stores a local clock time and, whenever the browser gets a chance to run, checks the interval against your device clock. If the selected time passed while the tab was backgrounded, the alarm rings on that next check instead of drifting by the number of delayed ticks.
Use a browser alarm safely
A web page cannot wake a computer that is sleeping, shut down or closed, and browsers may require an interaction before they allow sound. Use Test sound after opening the page, keep the tab open, and make sure the device volume is on. For an appointment or flight that cannot be missed, use the operating system or phone alarm as a backup. This tool is most useful for desktop reminders, breaks, meetings and short naps while the device stays awake.
Multiple alarms stay local
You can keep up to 12 enabled or paused alarms here, each with an optional label such as “Stand-up” or “Take laundry out.” They repeat at the selected local time on later days until you disable or remove them. The list is stored only in this browser using local storage; it is not sent to a server, does not sync to another device, and can disappear if you clear this browser’s site data.
Frequently asked questions
Will an online alarm ring in a background tab?
Yes. This alarm compares the scheduled local time with the device clock when the browser runs again, so it can alert after a background-tab delay. The tab must stay open and the device must remain awake.
Can I set more than one alarm?
Yes. You can add up to 12 labeled alarms, enable or disable each one separately, and see the next enabled alarm above the controls.
Are my alarms saved after a refresh?
Yes. Alarm time, label and enabled state are saved only in this browser, so they are restored after a refresh. Clearing this site’s browser data removes them.
Will this alarm wake a sleeping laptop?
No. A browser tab cannot run while a laptop or computer is asleep, shut down or closed. Keep the device awake and use a built-in alarm as backup for important wake-ups.
Does the online alarm need an internet connection?
After this page has loaded, alarm scheduling and sound generation run in the browser. The alarm list and labels stay on the device and are not sent anywhere.
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Updated 2026-10-28