What Is an Online Alarm Clock?
An online alarm clock is a web-based tool that lets you set a time-based alert directly in your browser — without installing any app. TrueTime.zone's alarm clock works on any device with a modern browser: desktop, laptop, tablet, or smartphone.
Simply choose a time, pick a sound, and click Set Alarm. When the time arrives, your browser will play the alert sound. Keep the tab open for the alarm to ring.
How to Set an Online Alarm
- Step 1: Enter the alarm time using the time picker above.
- Step 2: Select your preferred alarm sound.
- Step 3: Optionally, add a label to remember what the alarm is for.
- Step 4: Click Set Alarm and keep this tab open.
- Step 5: When the alarm rings, click Stop or Snooze.
Features
- ✅ Completely free — no registration required
- ✅ Works on any browser and device
- ✅ Multiple alarm sounds to choose from
- ✅ Add a label to each alarm
- ✅ Set multiple alarms at once
- ✅ Snooze functionality
- ✅ Dark mode design — easy on the eyes
Frequently Asked Questions
Do I need to install anything?
No. TrueTime.zone is a fully browser-based alarm clock. Just open the page, set your alarm, and keep the tab open. No installation, no sign-up, no subscription.
Will the alarm work if I lock my screen?
On most desktop browsers the alarm will still ring even with the screen locked, as long as the browser tab remains open. On mobile devices, browsers may be paused by the operating system — for critical wake-up alarms, we recommend using your phone's native alarm app as a backup.
What happens if I close the tab?
If you close the browser tab, the alarm will not ring. The alarm runs entirely inside your browser session. Keep the tab open and your computer or device active.
Can I set multiple alarms?
Yes. You can set more than one alarm at a time. Each alarm will ring at its scheduled time. You can cancel any alarm by clicking the × button next to it.
Is the alarm clock free?
Yes, completely free. TrueTime.zone is supported by display advertising, so all tools — including the alarm clock — are available at no cost.
Does it work on mobile?
Yes. The online alarm clock is fully responsive and works on iPhone and Android browsers. Open the page in Chrome or Safari on your phone, set the alarm, and leave the screen on for best results.