Set the alarm clock for 11:58 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 11:56 am Alarm clock for 11:57 am Alarm clock for 11:59 am

Going to bed for a 11:58 am alarm

Asleep by 2:43 am — 6 full sleep cycles, about 9 hours
Asleep by 4:13 am — 5 full sleep cycles, about 7 hours
Asleep by 5:43 am — 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.

11:58 am across the country

Sydney	11:58 am
Brisbane	11:58 am
Adelaide	11:28 am
Perth	9:58 am
Darwin	11:28 am

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

Online alarm clock for 11:58 am

As you hand the koala recovery centre tour to the next guide at 11:58 am, the alarm can mark the changeover without interrupting your final explanation. The two minutes before 12:00 pm leave enough time to pass along visitor numbers, any accessibility needs and notes about animals currently resting away from public areas.

Because this alarm runs in your browser, its sound depends on the page remaining open and your phone or computer staying awake. If you close the tab or browser, or let the device sleep, the tour handover may pass without an alert. Keep the page visible, leave the sound turned up and connect the device to power if it is running low. A quick audio check also confirms that silent mode will not swallow the signal.

A late-morning change of guide can coincide with rising Australian heat outside and strong air conditioning inside the centre. Before the next tour begins, the outgoing guide can mention which paths are exposed to the sun and which rooms feel noticeably cooler. Keeping a light layer and water nearby makes it easier to move between those spaces, while the 11:58 am alarm preserves a clear moment for the handover.

Common questions

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.

Is there a cost to use this?

No, it's free, with no sign-up and no limit on how many times you set it. It just needs the tab left open until the time you've chosen arrives.

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.