Online Alarm Clock — Free, In-Browser, No Install
An online alarm clock that runs entirely in your browser tab — no app, no account, no sign-up. Open the page, set the time, and keep the tab open until the alarm goes off. Your selection is remembered on return visits via localStorage.
Pick a sound from the catalog (or stay with the default), set a title for context, and toggle repeat if you want a fallback reminder. The main display is fullscreen-friendly for bedside use; mobile and desktop are equally supported.
The alarm triggers while this tab is in the foreground. If your device is locked or the tab is throttled, the alert may be delayed — see the FAQ below for critical wake-up backup suggestions.
Frequently asked questions
- How do I set an alarm on onetimer?
- Open /alarm, click Set Alarm (or Edit), choose a time using the 12/24-hour toggle, optionally set a title and a sound, then click OK. The countdown runs in this tab until the chosen time. To dismiss, click Stop on the alert overlay or press Esc.
- Will the alarm work if my computer sleeps?
- The alarm needs your device awake with this tab open. For critical wake-ups, disable sleep mode, keep the laptop plugged in, or use a dedicated alarm device as backup. The on-screen alert still appears when you return even if the audio was missed.
- Can I change the alarm sound?
- Yes. Open the alarm editor, switch the Sound dropdown to any of the 24 ringtone options grouped by Classic & Bells, Digital & Modern, Musical, Nature, Urgent & Loud, and Gentle & Fun. Use Try Alert to preview before relying on it.
- Is this alarm clock free?
- Yes. All alarm features — sound catalog, 12/24-hour toggle, fullscreen display, share/embed, repeat — are free with no subscription and no account.
- Does the alarm work on mobile?
- Yes. The alarm module is mobile-friendly out of the box — main display, editor, sound picker, and alert overlay all adapt to small screens. On most mobile browsers, the tab needs to stay open for the audio to fire reliably; closing the tab stops the alarm.