Set Alarm for 3:45 AM
A free online alarm clock preset to 3:45 AM. Press Start, leave this tab open, and it will ring at 3:45 AM sharp.
Keep this tab open. For alarms that work with your phone locked, get AVA.
Waking up at 3:45 AM
A 3:45 AM alarm is a specialist’s tool — a night-shift start, a flight to catch, a deadline on the other side of the world, or a short sleep wedged between two halves of a long day. It works, but it deserves backup: set a second alarm five minutes later until the routine is proven.
Sleeping toward 3:45 AM? Count cycles, not hours: asleep by 8:15 PM completes five, and even a single 90-minute cycle beats an hour of fragmented dozing. Set the alarm before your head hits the pillow — nobody does arithmetic well in the dark.
When it rings, act fast — darkness invites the return to sleep. Light on before anything else, then stand up. If you are staying up, find the brightest light you can; if this is a brief interruption, do the opposite and keep everything dim.
FAQ
- How do I set an alarm for 3:45 AM?
- Press Start above — the page counts down to the next 3:45 AM and plays a loud beep through your browser. Keep this tab open and your volume up. No download or signup needed.
- What time should I go to bed to wake up at 3:45 AM?
- To get 7.5 hours of sleep (five full 90-minute cycles), be asleep by 8:15 PM. For a full nine hours, aim for 6:45 PM. Add about 15 minutes for actually falling asleep.
- Will the alarm ring if my screen is off or the tab is closed?
- No — a browser alarm needs this tab open and the device awake. For alarms that ring reliably even over the lock screen, use the AVA app.