Set the alarm clock for 4:19 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 4:17 am Alarm clock for 4:18 am Alarm clock for 4:20 am Alarm clock for 4:21 am

Going to bed for a 4:19 am alarm

Asleep by 7:04 pm — 6 full sleep cycles, about 9 hours
Asleep by 8:34 pm — 5 full sleep cycles, about 7 hours
Asleep by 10:04 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.

4:19 am across the country

London	4:19 am
Birmingham	4:19 am
Manchester	4:19 am
Glasgow	4:19 am
Belfast	4:19 am

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

Online alarm clock for 4:19 am

Preparing ahead for a heating check in an old stone house, you can set this alarm for 4:19 am before you settle down. That gives you a clear prompt to inspect the boiler, radiators or thermostat at the planned moment, rather than watching the clock through the night. If you also need to review the settings at 5:00 am, treat that round hour as a separate check.

Before relying on the reminder for the house, check whether your headphones are still connected. The alarm sound may be routed to them without you noticing, especially if they were used earlier and left beside the computer. Set the volume, run a brief test, then leave the alarm page available. The heating check will have no audible reminder if you close the browser page or allow the computer to sleep.

An old stone house can feel different when the night air outside is damp, so note the outdoor humidity before changing the heating. At 4:19 am, open a window only briefly if you want to compare the air, then close it before judging the room temperature. This helps you avoid reacting to a temporary cold draught while checking whether the heating is working as expected.

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.