Set one or many alarms, repeat them on chosen weekdays and snooze when you need five more minutes. Everything runs in this tab and is saved on your device.
Online Alarm Clock
Set one or many alarms, repeat them on chosen weekdays and snooze when you need five more minutes. Everything runs in this tab and is saved on your device.
Alarm times, labels and settings stay on your device. They are saved in this browser's local storage and never sent to ArrayKit.
The Online Alarm Clock keeps a live clock with the full date and lets you add up to thirty alarms. Each one has a time, an optional label, repeat days from Monday to Sunday (or none for a one-off), a sound and a snooze of 5, 10 or 15 minutes. The list shows when every alarm rings next, such as in 8 h 20 min, and one-time alarms switch themselves off after they ring. The tab compares the real clock with your alarm times twice a second and again whenever it returns to view, so a tab that was suspended rings an alarm it missed, if the time passed within the last ten minutes. Alarms and settings are stored in this browser only. A browser cannot wake a closed tab, so keep it open.
Features
Live clock with seconds and the full date, switchable between 12-hour and 24-hour display
Multiple alarms, each with its own time, label, sound and snooze length
Repeat on any weekdays, with one-click Weekdays, Weekends and Every day
Shows when each alarm rings next, for example in 2 h 14 min
Loops the chosen alarm, chime or beep until you dismiss or snooze it
Rings an alarm missed by a suspended tab within ten minutes and says it was missed
Optional desktop notification, flashing tab title and a screen that stays awake while an alarm is set
Alarms saved in this browser's storage, with nothing sent anywhere
How to use the Alarm Clock
Pick a time and, if you like, type a label such as Wake up
Choose repeat days, or leave them empty for a one-time alarm, then press Add alarm
Press Test sound once so your browser allows audio, and set the volume
Keep the tab open; when the alarm rings, press Dismiss or Snooze
Example
Input
Alarm: 07:00 · Wake up · repeat Mon–Fri · snooze 10 min
It is Monday, 22:40
Output
07:00 Wake up
Weekdays · rings in 8 h 20 min
At 07:00: Dismiss, or Snooze 10 min (rings again at 07:10)
Minutes are rounded up, so the countdown in the list matches the clock on the wall.
Common errors & troubleshooting
The alarm showed up but made no sound. — Browsers block audio until you interact with the page. Press Test sound once, then check the volume slider, your device volume and that the tab is not muted.
The alarm did not ring while my computer was asleep. — A sleeping computer, a locked phone or a closed tab cannot run any page code. Keep the tab open, stop the device from sleeping and consider switching on Keep screen on.
A one-time alarm shows as off after it rang. — One-time alarms switch themselves off once they ring so they do not repeat tomorrow. Turn the toggle back on, or choose repeat days to keep it going.
The alarm rang a few seconds or even a minute late. — Browsers slow timers in background tabs, so the check can run late. The alarm still rings and shows the time it was due. Keep the tab in view for the most exact timing.
Frequently asked questions
Will the Online Alarm Clock ring if its tab is in the background?
Yes, as long as the tab stays open. It checks the real clock twice a second and again the moment you return to the tab. Some browsers slow hidden tabs, which can delay the sound by a few seconds, occasionally up to a minute.
Does the Online Alarm Clock work with a closed tab, a sleeping computer or a locked phone?
No. A web page can only run while its tab is loaded and the device is awake, and no site can override that. Leave the tab open, plug the device in, keep it from sleeping and turn the volume up.
How do I set a weekday-only alarm in the Online Alarm Clock?
In the Repeat row, press Weekdays, or tap the day chips you want. With no days chosen the alarm rings once at the next occurrence of that time; with days chosen it rings every week on those days.
Why is my Online Alarm Clock alarm silent?
Browsers only let a page play sound after you have clicked, tapped or pressed a key on it. Press Test sound once in this tab; the page also warns you when sound is not enabled yet and an alarm is waiting.
What does the Online Alarm Clock do if its tab was suspended when the alarm time passed?
If the time passed within the last ten minutes, it rings straight away and shows Missed at that time. If it was longer ago, it does not ring, but it leaves a note that the alarm was missed.
Where does the Online Alarm Clock keep my alarms?
In this browser's local storage only. They are not sent to ArrayKit or synced to other devices, and clearing your browser data removes them.
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