Set the alarm clock for 4:03 am

Leave this tab open — the alarm only rings while the tab stays open.

The alarm goes off in: ::

You can also try the other alarm clocks

Alarm clock for 4:01 am Alarm clock for 4:02 am Alarm clock for 4:04 am Alarm clock for 4:05 am

Going to bed for a 4:03 am alarm

Asleep by 6:48 pm — 6 full sleep cycles, about 9 hours
Asleep by 8:18 pm — 5 full sleep cycles, about 7 hours
Asleep by 9:48 pm — 4 full sleep cycles, about 6 hours

A sleep cycle runs about 90 minutes, and most people take around 15 minutes to drop off. Waking at the end of a cycle feels easier than waking in the middle of one.

4:03 am across the country

Sydney	4:03 am
Brisbane	4:03 am
Adelaide	3:33 am
Perth	2:03 am
Darwin	3:33 am

Times are worked out live in your browser, so daylight saving is already accounted for.

How to use the online alarm clock

Nobody sets an alarm for 4:03 am for fun. Maybe it's an early shift at the depot, a long drive before the roads get busy, or you're still awake and don't trust yourself to notice the time. Pick a sound, set it for 4:03 am, and this page will handle the rest while the house stays quiet.

There's a short list of sounds to choose from before you press Start — pick one that suits how deep a sleeper you are. Once it's set, the page keeps time in the background of your browser, and it'll sound at the moment you selected, provided the tab hasn't been closed.

Because this runs in the browser rather than on the phone's operating system, it sidesteps silent mode and do-not-disturb entirely, useful if your phone alarm has ever failed to go off for exactly that reason. Just be aware it needs the tab open and the screen or laptop lid to stay on to actually ring. On a 24-hour clock 4:03 am is written 04:03, and spoken aloud it's three minutes past four at night. You'll also see it written 4.03 am — a full stop instead of the colon means the same time. If you need it loud, turn the system volume up before you start: the alarm plays at whatever the device is set to.

Common questions

Will the alarm still ring if I close the browser tab?

No. The alarm only runs while this tab stays open — closing it, or closing the browser entirely, stops the countdown before it can ring. Keep the tab open in the background if you need it to go off later.

Does the alarm work if my laptop goes to sleep?

Not reliably. If the device sleeps or the screen locks, the browser tab pauses along with it, so the alarm may not fire on time or at all. Adjust your power settings if you're relying on this over a longer stretch.

Do I need to create an account or download anything?

No, there's nothing to sign up for and nothing to install. Pick a time and a sound, press Start, and it runs entirely in this browser tab.

Can I change the alarm sound?

Yes, there's a short list of tones to choose from before you press Start. Pick whichever one you're most likely to actually hear — softer sounds are easier to sleep through than a firm chime or bell.