Set the alarm clock for 6:38 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 6:36 am Alarm clock for 6:37 am Alarm clock for 6:39 am Alarm clock for 6:40 am

Going to bed for a 6:38 am alarm

Asleep by 9:23 pm — 6 full sleep cycles, about 9 hours
Asleep by 10:53 pm — 5 full sleep cycles, about 7 hours
Asleep by 12:23 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.

6:38 am across the country

London	6:38 am
Birmingham	6:38 am
Manchester	6:38 am
Glasgow	6:38 am
Belfast	6:38 am

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

How to use the online alarm clock

Getting the finish tokens laid out early for Saturday’s parkrun leaves room to check the sequence before runners arrive. Set the alarm for 6:38 am, then use the time before 7:00 am to place the tokens where the finish team can reach them and confirm that none are missing or stuck together.

While your hands are busy sorting finish tokens, the alarm sound can quietly route itself to connected headphones instead of the phone speaker. Check the audio output now and briefly test the volume so the signal will be audible from where you are working. A browser alarm cannot wake a sleeping phone or continue after its page has been dismissed, which could leave the finish tokens unfinished at departure time; keep the page active and use a separate alarm if the timing cannot be missed.

Preparing the finish area this early may mean stepping outside while the air still feels damp. Moisture can settle on token surfaces or make paper notes curl, so keep both inside a dry pouch until they are needed. If the morning air is cool and humid, allow a little extra time for carrying the kit and checking the course rather than leaving every outdoor task until the final few minutes.

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 6:38 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.