What time should I go to bed if I wake up at 2:00 pm?

Waking at 2:00 pm is a shift-worker's morning. Five cycles start at 6:15 am, six at 4:45 am — both in daylight, which makes blackout curtains the real bedtime tool.

Why three times and not one

The middle option, 6:15 am, is five cycles and 7 h 30 min of actual sleep; 4:45 am is six cycles and 9 h. Both sit inside the adult range. The 7:45 am option is 6 h: enough to get through the day, not enough to do it twice.

Sleep moves from light sleep into deep sleep and then REM, and one pass takes about 90 minutes — anywhere from 70 to 120 depending on the person and the point in the night. That spread is why these are windows, not appointments.

Walk through the night from a 6:15 am lights-out: asleep by about 6:30 am, into the first stretch of deep sleep around 6:50 am, first REM period near 7:45 am, the halfway point of the night at 10:15 am, and the longest REM period of the night starting around 1:25 pm — which is what a 2:00 pm alarm at the end of cycle 5 lets you finish.

All bedtimes for a 2:00 pm alarm

Formula: bedtime = wake time − (cycles × 90 min) − 15 min · adult range from the NSF 2015 panel and the AASM/SRS 2015 consensus · methodology

Who a 2:00 pm alarm fits: late closers and short-commute night workers

A 2:00 pm wake-up puts the five-cycle bedtime at 6:15 am, close to sunrise for much of the year. That timing works for two groups. People who close a bar, kitchen or venue and are home by 4 or 5 am can take the six-cycle option, 4:45 am, and be asleep before the street gets loud. People who finish a night shift at 6 am with a short trip home can make 6:15 am if they go straight to bed. If your shift ends at 7 am, neither is reachable: the realistic choice is the four-cycle 7:45 am, which is six hours of sleep, or a later alarm.

Going to sleep as daylight arrives is the hard part. Reviews of shift work name difficulty getting to sleep and shortened sleep as the commonest complaints, so darken the room before you leave for work, not when you get back. The six-hour caffeine line for a 6:15 am bedtime is 12:15 am: coffee in the first half of the shift, none in the second. And count forward as well as back. Up at 2:00 pm and at work again that night, you will have been awake 17 hours by 7 am, and the end of the night is where the same reviews place peak sleepiness. A short nap before leaving home shortens that stretch.

Every alarm in the 2 pm hour

Lights-out times for each alarm · last coffee = six hours before the five-cycle bedtime (Drake 2013) · full grid on the open data page

If you can't fall asleep by 6:15 am

If 6:15 am comes and your mind is still running, aim for the next cycle boundary at 7:45 am instead of counting the minutes. Ten to twenty minutes to fall asleep is normal; much longer, repeatedly, is worth a conversation with a clinician rather than a calculator.

Try a different time