Set the alarm clock for 3:03 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 3:01 am Alarm clock for 3:02 am Alarm clock for 3:04 am Alarm clock for 3:05 am

Going to bed for a 3:03 am alarm

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

3:03 am across the country

Sydney	3:03 am
Brisbane	3:03 am
Adelaide	2:33 am
Perth	1:03 am
Darwin	2:33 am

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

How to use the online alarm clock

Setting an alarm for 3:03 am while everyone else is asleep can feel like cheating the clock, but it's usually just planning ahead for an early departure or a shift that starts before sunrise. This will sound at 3:03 am through your speakers, whether it's the depths of winter or a short summer night.

Choose a sound before you press Start — something like a chime or a classic bell tends to work better than anything too gentle. Once it's running, the countdown happens right here in the browser, which means the tab needs to stay open in the background rather than being closed.

The advantage of a browser alarm is volume and reliability at a desk: laptop speakers are often louder and easier to hear across a room than a phone left in a bag. The catch is that it depends entirely on the tab staying open; if the browser closes or the laptop sleeps, the alarm won't fire. On a 24-hour clock 3:03 am is written 03:03, and spoken aloud it's three minutes past three at night. Timetables and rosters may show it as 03:03, and handwritten notes as 3.03 am. Set an alarm for 3:03 am, set the alarm to 3:03 am, set my alarm for 3:03 am — all of it lands on this page and does the same thing.

Common questions

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.

What happens once the alarm goes off?

It rings through your device's speakers on a loop until you stop it from this page. There's no separate app notification, so make sure your volume is turned up before you rely on it.

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.