Set the alarm clock for 7:23 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 7:21 am Alarm clock for 7:22 am Alarm clock for 7:24 am Alarm clock for 7:25 am

Going to bed for a 7:23 am alarm

Asleep by 10:08 pm — 6 full sleep cycles, about 9 hours
Asleep by 11:38 pm — 5 full sleep cycles, about 7 hours
Asleep by 1:08 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.

7:23 am across the country

London	7:23 am
Birmingham	7:23 am
Manchester	7:23 am
Glasgow	7:23 am
Belfast	7:23 am

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

How to use the online alarm clock

While preparing to raise the canal bridge for an approaching barge, set the alarm for 7:23 am before the signal is actually needed. That leaves the controls, navigation notes and immediate surroundings to check without rushing. If the movement is expected before 8:00 am, the alarm also gives the morning a clear reference point rather than relying on repeated clock checks.

Because the bridge operation depends on noticing the cue, test the alarm now at a low volume, then reset it for 7:23 am. This confirms that the chosen sound is audible from the control position and distinct from nearby machinery. Keep the browser alarm running and the computer awake; otherwise the barge cue will be missed. A separate established alarm is sensible if missing the signal would hold up canal traffic.

Before settling into the early shift, look at how daylight falls across the bridge controls and canal. At this hour, low morning light can leave labels dim while putting glare on glass or polished surfaces. Position a lamp so it illuminates the panel without reflecting into your eyes, and adjust blinds or a screen beforehand if sunrise will reach the workspace near 7:23 am. Keeping a torch within reach also avoids searching in a poorly lit corner when the alarm sounds.

Common questions

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.

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.