Online Alarm Clock
Free online alarm clock with a big live clock, multiple alarms, three ring tones and a 5 minute snooze. Set it in seconds - no app install needed.
Does the online alarm clock work if I close the tab?
No. The alarm runs on JavaScript inside this page, so it only rings while the tab stays open. Keep the tab open (and the device awake) for the alarm to go off.
Will the alarm ring if my computer goes to sleep?
In most cases no - browsers suspend timers when the system sleeps. Use the screen wake lock button, adjust your power settings, or leave the device plugged in overnight.
Do I need an internet connection for the alarm to ring?
After the page has loaded, the alarm works completely offline. The clock and ring tones are generated locally by your browser, with no server involved.
Are my alarms saved if I reload the page?
Yes. Alarms are stored in your browser's local storage on this device, so they survive a reload. Clearing site data or using private mode removes them.
Can I set more than one alarm?
Yes, you can add as many alarms as you like. Each one has its own time, optional label, ring tone and on/off switch, and can be deleted at any time.
What does the snooze button do?
Snooze silences the ringing alarm and schedules a new one-shot alarm 5 minutes later, so you get a short extra nap without losing the wake-up call.
Which ring tones are available?
Three built-in tones: Beep, Chime and Radar. They are synthesized in real time with the Web Audio API, so nothing has to be downloaded.
Is this alarm clock free and private?
Completely. It is free, needs no sign-up, and everything runs locally in your browser. No alarm times or labels ever leave your device.
How to Use Online Alarm Clock
Turn any browser tab into a full alarm clock. Set multiple alarms with different ring tones and labels, snooze when you need five more minutes - all processed locally on your device, nothing is uploaded.
- Check the current time on the big live clock at the top, switching between 24-hour and 12-hour format with the dropdown.
- Pick a time with the time field, optionally type a label (like 'Meeting'), choose a ring tone and press Add alarm.
- Manage your alarms in the list below: each has an on/off switch and a delete button, and alarms survive a page reload.
- Press Keep screen awake if you want to stop your screen from turning off while you wait.
- When the alarm rings, a full-screen alert appears - press Stop to dismiss it or Snooze 5 min for a short nap.
The alarm can only ring while this tab stays open and your device is awake, so keep the volume up and the tab in the foreground.
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