What time should I wake up if I go to bed at 4:00 am?

Going to bed at 4:00 am puts the wake-up in the middle of the day: 11:45 am after five cycles, 1:15 pm after six.

Why these alarm times

Setting the alarm for 11:45 am gives 7 h 30 min of sleep after the usual fifteen minutes to drift off — inside the 7–9 hours recommended for adults. 1:15 pm adds a sixth cycle (9 h). The earliest option, 10:15 am, is four cycles and 6 h — a one-night floor, not a routine.

Waking at the end of a cycle usually means waking from light sleep or REM rather than deep sleep, which is why an alarm that lands here feels gentler than one that lands twenty minutes earlier. Cycles vary from 70 to 120 minutes, so each time is the centre of a window.

In clock terms: lights out 4:00 am, asleep around 4:15 am, deepest sleep of the night between roughly 4:35 am and 5:45 am, the night's midpoint at 8:00 am, and REM building toward 11:10 am. The 11:45 am alarm lands as cycle 5 closes, so you are likely in light sleep rather than deep.

All alarm times for a 4:00 am bedtime

Formula: alarm = bedtime + 15 min + (cycles × 90 min) · methodology

A 4:00 am bedtime: closing shifts, late nights and a morning you sleep through

Lights out at 4:00 am is routine for people who close restaurants, bars and venues, for evening-shift workers who need a couple of hours to come down after a midnight finish, and for students and gamers who have drifted there. The alarms are 11:45 am for five cycles, 1:15 pm for six and 10:15 am for four. If your next shift starts at 4 or 5 pm, even the six-cycle alarm leaves the afternoon free, so the nine-hour option is realistic here in a way it rarely is for day workers.

Two things work against a 4:00 am sleeper. Sunrise arrives roughly one and a half to three and a half hours after lights out, depending on the season, so curtains matter more than for any evening bedtime. And the back half of the sleep runs through an ordinary morning: by 9 am you are in the lighter, REM-heavy cycles and the building is at its noisiest. If you keep waking at 9 or 10 and cannot get back, that is close to the four-cycle row, 10:15 am, and the practical fix is steady sound and a darker room, not an earlier night you will not keep. The caffeine line for 4:00 am is 10:00 pm, which for bar and kitchen staff is the middle of service; the late-shift coffee or energy drink is the one to drop first. If 4:00 am is drift and not work, the way back is the alarm, not the bedtime: hold 10:15 am for a few days and the bedtime follows.

Try a different bedtime