Set the alarm clock for 9:43 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 9:41 am Alarm clock for 9:42 am Alarm clock for 9:44 am Alarm clock for 9:45 am

Going to bed for a 9:43 am alarm

Asleep by 12:28 am — 6 full sleep cycles, about 9 hours
Asleep by 1:58 am — 5 full sleep cycles, about 7 hours
Asleep by 3:28 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.

9:43 am across the country

London	9:43 am
Birmingham	9:43 am
Manchester	9:43 am
Glasgow	9:43 am
Belfast	9:43 am

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

How to use the online alarm clock

While you watch the clock for the moment to return your books to the mobile library, an alarm set for 9:43 am lets you stop checking every minute. It marks a precise point in the morning, with 17 minutes still available before 10:00 am for gathering the books, finding your library card and getting ready to meet the van.

Your book-return reminder needs to be heard above whatever is already happening nearby. The alarm volume follows the sound level available through your browser and phone or computer, so a radio, kettle or busy household can mask it. A brief sound check at the same volume helps reveal that problem before 9:43 am. If this page is dismissed or the phone or computer falls asleep, no signal can play, and the books may miss the mobile library visit.

As the mobile library time approaches during the morning, notice whether changing daylight has made the screen difficult to see or easy to overlook. Positioning the phone where indirect daylight reaches it, rather than leaving it in glare or a dim corner, makes the alarm display clearer. Adjusting the curtains beforehand can also prevent a sudden patch of sunlight from hiding the on-screen alert at 9:43 am.

Common questions

What happens if my laptop goes to sleep before 9:43 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.

Will it still be right when the clocks change?

Yes. It reads your device's local clock, so the move between GMT and BST at the end of March and October is picked up automatically, as long as the computer's date, time and time zone are set correctly.