Alarm Clock

This is an alarm clock that runs inside a browser tab. The top of the page shows your device's current time (hours, minutes, seconds), and you can add several alarms, each with a time and an optional name. When one goes off, it keeps ringing and shows a system notification until you confirm each alarm. It suits timed reminders while you work at a computer, such as 'stand up and stretch at 15:30' or 'send the daily report at 17:50'. Its limits should be clear from the start: it depends on the page staying open. It is not a phone or operating-system alarm, so it will not ring if you close the tab, the computer sleeps or the browser is suspended. Do not rely on it to wake you in the morning or for reminders you cannot afford to miss.

How to use it

1. Optionally type a name in 'Alarm name', such as 'Wake up' or 'Drink water reminder'. Blank names show as 'Alarm'.
2. Pick hours and minutes in the time field below it. The default is 08:00.
3. Click 'Add alarm'. The first time, your browser may ask for notification permission, and allowing it is a good idea so you still see alerts when you are in another window. The 'Alarms' list gains an entry showing the time and the name.
4. The bell icon on the left of each entry is a switch: click it to turn that alarm off (a crossed-out bell) and click again to turn it back on. The trash icon on the right deletes it.
5. When an alarm goes off, a panel at the top lists the ringing alarms, each with a 'Confirm & dismiss' button. An alarm stops only when you click it, and several alarms that fire together must be confirmed one by one.

A typical scenario

Suppose you have a meeting at 15:00 and want a heads-up at 14:50. Add two alarms: 14:50 named 'Prep for meeting' and 15:00 named 'Meeting'. Carry on with other work, even in other tools on this site. Around 14:50:00 the page starts ringing at intervals and the browser shows an 'Alarm reminder' notification containing the alarm name (or the time when there is no name). Click 'Confirm & dismiss' and the 14:50 alarm stops. The 15:00 alarm remains on and will ring when its time comes.

Supported scope and known limits

• The alarm list is saved in your browser's local storage and is restored after a reload, closing the tab or reopening the browser; alarms that were ringing and not yet confirmed are restored too. Clearing site data, switching browsers or using a private window does not keep them.
• There are no repeat rules and no snooze. An enabled alarm rings again at the same time on following days (once per alarm per day), with no need to re-add it. To stop it, switch it off with the bell or delete it.
• An alarm rings whenever the current time is within the alarm's minute (it does not have to be exactly second 0) and it has not rung yet today, so a clock update that arrives a few seconds late no longer causes a miss. Which alarms have already rung today is saved, so reloading does not make them ring again. However, if nothing runs for the whole minute (the computer sleeps, the tab is frozen or the page is closed), that minute's alarm does not ring and is not made up afterwards.
• Time is the device's local time, shown in 24-hour format. If the device clock is wrong, the alarm is wrong.
• Alarms set for the same time ring together and each must be confirmed. If you click add with an empty time field, you get a useless alarm that never rings, so make sure a time is set.
• The sound is a simple browser-generated tone (about every 1.5 seconds) with no choice of ringtone and no volume control. Notifications need permission and their text follows the page language (English when the URL starts with /en, otherwise Chinese).
• Mobile browsers restrict background pages heavily. With the screen locked or another app in front, the alarm may not ring, so do not count on it to wake you on a phone.

FAQ: Can I use it as a morning wake-up alarm?

Not recommended. A web alarm needs the tab open, the device awake and the sound unmuted, and if any of those fails, it fails. For anything you absolutely cannot miss, use your phone's built-in alarm or a dedicated clock, and treat this tool as a helper while you work.

FAQ: Will it still ring if I switch to another site's tab?

Usually yes, as long as the tab has not been closed or frozen by the browser for a long period. Moving between tools on this website does not affect alarms, because their state is held at site level. Browsers slow timers in background tabs, but an alarm can fire at any second within its minute, so it is rarely missed; it is only lost if nothing runs for the whole minute, so keep a backup for important reminders.

FAQ: Why do I have to click 'Confirm & dismiss'?

So that you cannot miss it by accident. The tool keeps ringing and uses a notification that stays until it is closed, and it is closed only after you confirm. If you want a single beep and be done, this is not the right tool.

FAQ: What does the alarm name do?

The name appears in the list, in the ringing panel and in the system notification. When several alarms are ringing at once, the notification joins their names (or times, if they have none) together. A name cannot be edited after adding, so delete the alarm and add it again if you want to change it.

Privacy and processing

Alarm times, names, on/off state and a record of which alarms have rung today are kept in your own browser's local storage. The code sends none of it to a server, and clearing site data removes it. The clock reads your device's local time, and both the notification and the sound are produced by your own browser on your own machine.