Online Alarm Clock
Set a time below, then click Set Alarm - this rings (with an on-screen alert and a sound) when your computer's clock reaches that time.
Last updated: September 5, 2026
Frequently asked questions
Does this alarm clock keep the correct time?
Yes - it reads your computer or phone's system clock directly, so it's as accurate as your device's clock, updated every second.
Will the alarm still ring if I switch browser tabs?
Yes, as long as this tab stays open - the check runs in the background even on an inactive tab. Closing the tab or your browser cancels the alarm.
Can I set more than one alarm at a time?
This tool supports one alarm at a time - set a new one and it replaces the previous one. For multiple simultaneous countdowns instead of a specific clock time, use the Online Timer.
Is this an 'alarm clock website' I can bookmark and reuse?
Yes - this page works as a standalone browser alarm clock you can bookmark; just keep the tab open while you wait for it to ring, since the alarm only runs while the page is loaded.
Can I set an alarm for a time that's technically tomorrow, like 1:00 AM?
Yes - if the time you set has already passed today, the alarm automatically targets that time tomorrow instead, so setting 1:00 AM at 3:00 PM today will ring the following night.
Will the volume or sound be loud enough to wake me up if I'm asleep?
It plays through your device's normal audio output at whatever volume your system is set to, so it's best suited for staying alert during the day rather than relied on as a guaranteed wake-up alarm for deep sleep.
How is this different from my phone's built-in alarm app?
A phone's native alarm app keeps working even if the phone is locked or the browser is closed, while this browser-based alarm only rings while its tab stays open - use it for quick reminders at your computer, not overnight wake-ups.