Help & FAQ
Everything you need to know about using Online Alarm Clock.
Features
Alarm Clock
Set multiple alarms with custom labels, sounds and snooze options. Choose repeat schedules — once, daily, weekdays, weekends or specific dates. Your alarms are saved in your browser and work completely offline.
Countdown Timer
Start a precise countdown timer for cooking, studying, workouts or meetings. The timer plays an audible alert when it reaches zero. Works in the background while you use other browser tabs.
Stopwatch
Measure elapsed time with millisecond precision. Record lap times for sports and fitness activities. The stopwatch continues running even if you switch to another tab.
World Clock
See the current time in any city or timezone around the world. Useful for scheduling international calls and meetings. Search from hundreds of cities and time zones.
Frequently Asked Questions
Does the online alarm clock work when the browser tab is closed?
The alarm fires while the browser tab is open. To receive alerts with the tab in the background, allow browser notification permissions when prompted. Closing the tab completely will stop alarms from firing.
Will my alarms work offline or without internet?
Yes. Once the page has loaded, it works fully offline. All alarms are stored locally in your browser — no account or internet connection needed.
Can I set multiple alarms at the same time?
Yes. You can create as many alarms as you like, each with a different time, label, sound and repeat schedule. Toggle any alarm on or off without deleting it.
What sounds are available for alarms?
Choose from several built-in sounds including beep, digital, chime, birds and rain. You can also upload your own audio file to use as a custom alarm sound.
Can I set a recurring alarm for weekdays only?
Yes. When creating an alarm select the Recurring option, then choose Weekdays to have the alarm fire Monday through Friday automatically.
Is this alarm clock free to use?
Completely free. No account, no subscription and no download required. Open the page in any modern browser and start using it immediately.
Why didn't my alarm go off?
The most common reasons are: the browser tab was closed, your device was on silent or Do Not Disturb mode, or the browser blocked audio autoplay. Keep the tab open and grant notification permissions for the most reliable experience.
Can I use this on my phone?
Yes. The app works in any modern mobile browser on Android and iOS. For the best experience keep the browser tab open and screen active, as mobile browsers aggressively suspend background tabs.
Is my alarm data stored on your servers?
No. All alarm data is stored exclusively in your browser's local storage. Nothing is sent to any server. Clearing your browser data will erase your alarms.
How do I delete all my alarms?
You can delete alarms one by one from the Alarms tab. To wipe everything at once, clear your browser's site data for this page in your browser settings.
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