Online Alarm Clock
Free online alarm clock — set a time, label and sound, and your browser rings with a big live clock and countdown. No install or signup.
About the Online Alarm Clock
This online alarm clock turns your browser tab into a reliable alarm: pick a time, choose from three alarm sounds (classic beep, soft chime, or digital pulse), add an optional label like 'Stand-up meeting', and click Set. A large live clock shows the current time, and once armed, the display counts down the hours, minutes and seconds remaining.
When the alarm time arrives, the tab rings repeatedly until you stop it, and the tab title changes so you notice even from another tab. If you set a time that has already passed today, it's automatically scheduled for tomorrow — exactly how phone alarms behave. A test button lets you preview the sound and volume before you rely on it.
It's perfect for naps at your desk, cooking, timed exams, meeting reminders and pomodoro-style breaks when you don't want to reach for your phone. The whole thing runs client-side in your browser — just keep the tab open and the volume on.
How to Use the Online Alarm Clock
- 1Set the alarm time and optionally add a label and pick a sound.
- 2Click Test sound to check your volume, then Set alarm.
- 3Watch the live clock and remaining-time countdown — the tab title shows the alarm too.
- 4When it rings, click Stop alarm; use Cancel anytime before that.
Frequently Asked Questions
Will the alarm ring if I switch to another tab?
Yes — the alarm checks real clock time several times a second, so switching tabs or windows doesn't break it, and the tab title switches to 'Wake up!' so you notice visually too. Just keep the tab open: closing the tab or laptop lid stops any web alarm.
Why doesn't my alarm make any sound?
Browsers require a user interaction before a page may play audio — clicking Set alarm or Test sound satisfies that, so always set the alarm with a click and check your device volume and mute switch. The Test sound button is the quickest way to confirm everything is audible before you depend on it.
What happens if I set a time earlier than now?
It's scheduled for tomorrow automatically, the same convention phone alarms use. The countdown display always shows exactly how long until it rings, so you can confirm at a glance that it armed for the moment you intended.
Will the alarm work if my computer goes to sleep?
No — a sleeping computer suspends the browser, so the alarm can't fire until it wakes (some browsers then ring immediately on wake, but late). For overnight alarms keep the machine awake and volume up, or use a phone alarm as backup; this tool shines for at-your-desk reminders and naps.
How long does it ring before stopping?
It keeps ringing until you press Stop — a repeating pattern every couple of seconds rather than a single beep you might miss. The ringing screen also shows your label prominently so you remember why it's going off.