How to use the online alarm clock
Three in the morning has its own kind of silence, and an alarm for 5:18 am breaks it on purpose. Whether you're catching a pre-dawn flight or grabbing a short nap before a long haul, this tool rings at 5:18 am through your browser so you're not relying on a phone across the room.
Pick whichever sound you're most likely to actually notice, then press Start. The alarm is tied to this browser tab, so it needs to stay open. Minimising the window is fine, but closing the tab or the browser will stop the countdown before it ever rings.
Some people use this alongside a phone alarm rather than instead of it: a louder backup through laptop speakers, or a way to set a reminder without touching a phone at all. It won't survive the tab closing or the device sleeping, so for anything critical overnight, keep a second alarm running as well. On a 24-hour clock 5:18 am is written 05:18, and spoken aloud it's eighteen minutes past five in the morning. You'll also see it written 5.18 am — a full stop instead of the colon means the same time. Setting the alarm to 5:18 am tomorrow morning works the same way: if the time has gone for today, the count runs through to it.
Common questions
Is this alarm accurate across daylight saving time?
It uses your device's local clock, so as long as your computer's time and date settings are correct, it'll adjust automatically when daylight saving time starts or ends.
Can I use this on my phone instead of a laptop?
Yes, it works in a mobile browser the same way, but phones are more likely to lock the screen or sleep, which can stop the alarm from ringing. A laptop or desktop tends to be more reliable for this.
Can I set more than one alarm at a time?
This page is built around a single alarm at a time. For multiple alarms, open a separate tab for each one and set a different time in each, keeping every tab open until it's rung.
Why use a browser alarm instead of my phone's built-in one?
Mainly for reliability against silent mode, do-not-disturb, or a phone left charging out of earshot. It's a useful backup or a desk-based alternative, though it depends on this tab staying open rather than running in the background of your phone.