Online Alarm Clock

What this tool does

Online Alarm Clock lets you set a daily alarm time, shows a live countdown until it triggers, and plays a repeating sound with an on-screen banner when it goes off, intended for a quick browser-based reminder, not a replacement for your device’s native alarm when the tab might be closed.

A quick alarm while actively working in a browser, for a reminder, a short break, or a scheduled check-in, doesn’t need a phone app, just a tab that counts down and alerts you when the time comes.

This clock lets you set a daily alarm time, shows a live countdown until it triggers, and plays a repeating sound with an on-screen banner once it goes off, as long as this tab stays open and unmuted.

How to use Online Alarm Clock

1. Set your desired alarm time.
2. Toggle it on.
3. Watch the live countdown until the alarm time arrives.
4. Dismiss the on-screen banner once it sounds.

Tips for better results

• This alarm only works while the tab stays open in your browser, it cannot wake a sleeping device or ring from a fully closed tab, unlike a phone’s native alarm app.
• Use the Test sound button to confirm your volume and audio setup are working correctly before relying on the alarm for something time-sensitive.
• For anything you genuinely can’t risk missing, use your device’s built-in alarm instead, this tool is best suited to a quick reminder while you’re actively working in the browser already.
• The alarm is set for a specific time of day and will trigger at that time whenever the next occurrence comes around while the toggle is on, not a one-time countdown from now.

Common use cases

• Setting a quick reminder while actively working in a browser tab.
• Scheduling a check-in alert for a specific time without reaching for a phone.
• Timing a break or task transition during a work session.
• Testing what an alarm sound and timing setup would feel like before relying on a more permanent solution.

Common mistakes to avoid

• Relying on this for something genuinely critical that you can’t afford to miss, like waking up for an important appointment, a phone’s native alarm app is the appropriate tool for that, since it works even if the browser or device sleeps.
• Muting the tab or browser and then being surprised the alarm didn’t audibly go off, the sound requires the tab to be open and unmuted to actually play.
• Closing the laptop lid or letting the device sleep and expecting the alarm to still trigger, browser timers generally pause under those conditions.