Set the alarm clock for 3:47 am

 

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

The alarm goes off in: ::
 
 

Going to bed for a 3:47 am alarm

  • Asleep by 6:32 pm — 6 full sleep cycles, about 9 hours
  • Asleep by 8:02 pm — 5 full sleep cycles, about 7 hours
  • Asleep by 9:32 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.

3:47 am across the country

London3:47 am
Birmingham3:47 am
Manchester3:47 am
Glasgow3:47 am
Belfast3:47 am

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

How to use the online alarm clock

As you finish up and head out to meet the Belfast ferry in Liverpool, a 3:47 am alarm gives the departure a firm starting point. That leaves a short, useful window before 4:00 am for putting on a coat, picking up your keys and checking the vehicle is ready. The alarm marks the moment to leave rather than another stage of getting prepared.

Because this ferry pickup depends on waking at the chosen time, the browser needs to remain active until the alert sounds. If the browser is dismissed or your phone settles into sleep, the ferry alarm may never sound. Keeping the device connected to power and preventing automatic sleep reduces that risk; a separate alarm on the phone or bedside clock provides sensible backup for a journey that cannot simply be delayed.

Reaching the terminal during the night may take less time than in daytime traffic, but roadworks, diversions and reduced overnight access can still alter the route. Check the expected journey time before settling down, then allow a little extra for parking and finding the correct arrivals area. At 3:47 am, quiet roads can make progress easier while unfamiliar signs and closed approaches make last-minute navigation slower.

Common questions

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 3:47 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.

Can I change the sound?

Yes, there is a short list of tones to pick from before you press Start. Softer sounds are easy to sleep through, so a firmer bell tends to be the safer choice for anything early in the morning.