Set the alarm clock for 3:21 am

 

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

The alarm goes off in: ::
 
 

Going to bed for a 3:21 am alarm

  • Asleep by 6:06 pm — 6 full sleep cycles, about 9 hours
  • Asleep by 7:36 pm — 5 full sleep cycles, about 7 hours
  • Asleep by 9:06 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.

3:21 am across the country

London3:21 am
Birmingham3:21 am
Manchester3:21 am
Glasgow3:21 am
Belfast3:21 am

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

How to use the online alarm clock

Preparing at 3:21 am gives you time to check your flask, warm layers and torch before heading onto the heath to watch the meteor shower. Set the alarm now, while the plan is clear, and use the approach to 4:00 am for those final checks rather than watching the clock in the dark.

Your meteor-watching plans determine whether a gentle chime or a persistent sound makes sense. A softer tone suits an alarm kept close beside you, while a firmer one may help if you are likely to drift off before leaving. Check the volume with a brief test first. The meteor shower alarm cannot prompt your departure if the browser page has been closed or your phone has gone to sleep, so keep both active until it sounds.

Leaving for the moorland in the middle of the night can easily disturb sleeping people elsewhere in the house. Put clothes, keys and outdoor gear together beforehand, silence loose items, and keep the phone within reach so the alarm can stay relatively quiet. At 3:21 am, avoid bright room lighting and noisy last-minute searches; a dim torch aimed towards the floor lets you gather everything with less disruption.

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.