About the Online Alarm Clock
This online alarm clock rings at a time you choose, right in your browser. Pick the time, add a label if you like, and press Set alarm. A large clock shows the current time, a countdown shows how long is left, and when the time arrives a loud beep sounds with Stop and Snooze buttons for 5, 10 or 15 minutes. The page title also changes to Alarm so you can spot it in another tab. Because it runs in the page, you need to keep the tab open and the sound on. It is good for naps, cooking, study breaks and reminders at a desk.
Updated October 2026
How to use the Online Alarm Clock
- 1Choose the alarm time. You can include seconds.
- 2Optionally type a label such as Tea or Meeting.
- 3Press Set alarm.
- 4Keep this page open with the sound on until the alarm time.
- 5When it rings, press Stop or choose a snooze time.
Making sure it works
- Set a test alarm a minute ahead to check the sound.
- Keep the tab open, and avoid putting the computer to sleep.
- Turn up the volume and unmute the tab in the browser.
- Plug in a laptop, since long alarms use battery.
- Check the time zone of your device, because the alarm uses your device clock.
When to use an online alarm
An online alarm suits short waits and desk work: a reminder before a meeting, a nap while working at home, a break during study sessions or an alarm for something in the oven when you are near the computer. It is not a substitute for an overnight alarm, since computers sleep and browsers pause background pages. For serious wake-ups, use a device alarm with backup.
Related tools
The Countdown Timer counts down from a duration, the Pomodoro Timer helps you work in focused blocks, the Stopwatch measures elapsed time, the Online Clock shows the time in large digits and the Time Zone Converter helps schedule across countries. The Tone Generator can help you test your speakers.
Features
- Alarm for any time of day
- Live clock and countdown
- Loud repeating beep
- Snooze for 5, 10 or 15 minutes
- Optional label shown when it rings
- Page title changes when the alarm rings
- Nothing sent anywhere
Frequently asked questions
Will the alarm ring if I close the page?
No. The alarm runs inside this web page, so the tab must stay open. Leave it open in the background of your browser, make sure the computer is awake and not muted, and check that your browser is allowed to play sound.
Will it work on my phone?
It can, but phones often pause web pages when the screen is locked or the browser is in the background, so the alarm may not sound. For waking up, use your phone's built-in alarm. This tool is best on a desktop or laptop, or for short timers while using the screen.
Why did I not hear the sound?
Browsers only allow sound after you have interacted with a page, which is why you need to press Set alarm. Also check that the volume is up, the tab is not muted and no other app is blocking audio. Test with an alarm one minute ahead.
What happens if I set a time that has already passed today?
The alarm is set for the next time that clock time comes round, which is tomorrow. If it is 10:00 now and you set 07:30, the alarm rings at 07:30 the next morning and the countdown shows how many hours remain.
Can I set several alarms at once?
This page keeps one alarm at a time. Press Change alarm to set a new one. For repeated timed intervals, use the Pomodoro Timer, or for a quick countdown try the Countdown Timer.
Is my information stored?
No. The time and label stay in this page and are gone when you close it. Nothing is sent to a server, and the beep is generated in your browser.