caldays
Online alarm clock

Set an alarm — right in your browser.

Free online alarm clock. Pick a time, keep this tab open, and the alarm rings with sound (and a notification if you allow it). Nothing to install, no account, works offline once loaded.

Current time

Your local time now

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Alarm

Set your alarm time

Keep this tab open — browsers only run timers in open tabs. For sound, interact with the page at least once (browser autoplay policy).

Frequently asked questions

Does the alarm work if I close the tab?
No. Web pages can only run while open. Keep the tab open (it can be in the background on desktop). For phone alarms, your built-in clock app is more reliable.
Why is there no sound?
Browsers block audio until you interact with a page. Click anywhere (e.g. the Start alarm button) and sound will be allowed.
Does it work offline?
Yes — once the page is loaded, the clock and alarm run entirely in your browser. No data is sent to any server.

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Free, no install
Online alarm clock