Set the alarm clock for 4:47 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 4:45 am Alarm clock for 4:46 am Alarm clock for 4:48 am Alarm clock for 4:49 am

Going to bed for a 4:47 am alarm

Asleep by 7:32 pm — 6 full sleep cycles, about 9 hours
Asleep by 9:02 pm — 5 full sleep cycles, about 7 hours
Asleep by 10:32 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.

4:47 am across the country

London	4:47 am
Birmingham	4:47 am
Manchester	4:47 am
Glasgow	4:47 am
Belfast	4:47 am

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

How to use the online alarm clock

You have only just woken at 4:47 am, with the tent check still ahead after a storm in the Lake District. The alarm marks the moment to sit up, find a torch and pull on waterproofs before stepping outside. By 5:00 am, there should be enough early light to inspect guy lines, pegs and pooled water without rushing through the dark.

Your tent round depends on hearing the alert, so check where the browser’s sound is being sent when setting it. Headphones left connected can take the alarm unnoticed, especially if they are under bedding or packed in a bag. Keep the volume audible through the intended speaker and test it briefly. If the browser is closed or the phone goes to sleep, the alarm cannot sound, and the tents may remain unchecked when you meant to get moving.

Before a wet, pre-dawn walk around camp, a few sips of water and a small, familiar snack are practical if you are hungry. Leave a full cooked breakfast and very hot drinks until the storm check is finished: at this hour, carrying a mug among ropes and muddy pitches adds an avoidable distraction. Put water somewhere easy to reach on your return, then focus on secure footing and visible damage outside.

Common questions

Can I use this on a phone?

It works in a mobile browser, but phones lock the screen and suspend background tabs far more readily than a laptop does, which can stop the alarm sounding. For anything important, a desktop or a plugged-in laptop is the steadier option.

Does the alarm still work if I close the tab?

No. Everything runs inside this page, so closing the tab — or quitting the browser altogether — ends the countdown there and then. Leaving it open in the background is all it asks, and switching to another tab makes no difference.

What happens if my laptop goes to sleep before 4:47 am?

The tab sleeps along with it and the alarm will not sound on time, if at all. If you are relying on it, change the power settings so the machine stays awake, or keep a phone alarm running as well.

Do I need an account or an app?

Neither. Choose a time and a sound, press Start, and it runs in this browser tab. Nothing is downloaded, nothing is registered, and closing the page leaves nothing behind on the device.