Sleep Cycle

Sleep Cycle Calculator · Wake up at 6 AM

What time should you go to bed to wake up at 6 AM?

To wake up at 6:00 AM feeling refreshed, go to bed at 8:45 PM (6 sleep cycles, 9 hours) or 10:15 PM (5 cycles, 7.5 hours). Both times land your alarm at the end of a 90-minute cycle instead of mid-cycle — which is what stops the grogginess. Times assume about 15 minutes to fall asleep.

Your night, if you wake at 6 AM

Light / REM Deep
Bed 10:15 PMWake 6:00 AM · end of cycle 5

Every cycle-aligned bedtime for a 6 AM wake-up

Assuming ~15 minutes to fall asleep. Adjust below with the calculator.
Go to bedCyclesTotal sleep
8:45 PMBest69h
10:15 PMBest57.5h
11:45 PM46h
1:15 AM34.5h
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The math is easy. Winding down in time is the hard part.

6 AM is the classic office-worker alarm, and the real reason people miss their cycle isn't the arithmetic — it's that they decide to sleep at 10:15 PM but are still on their phone at 10:14. If 10:15 PM is your target lights-out, start winding down — screens off, lights low, no more email — by 9:30 PM. Treat that earlier time as the real "bedtime"; the number in the table is just when your eyes should already be closed.

Different wake-up time? Recalculate

Change the wake-up time or drag the slider to match how long you take to fall asleep.

15 min

Questions about a 6 AM wake-up

What time should I go to bed to wake up at 6 AM?

Go to bed at 8:45 PM for six cycles (9 hours) or 10:15 PM for five cycles (7.5 hours). Five cycles suits most adults. Both times target the end of a 90-minute cycle so you wake in light sleep.

Is 10:15 PM enough sleep before 6 AM?

10:15 PM to 6 AM is 7.5 hours of sleep across five full cycles, within the 7–9 hours recommended for most adults — and timed so your alarm doesn't interrupt deep sleep.

I can't sleep before midnight. What's my best option?

Go to bed at 11:45 PM for four complete cycles (6 hours). Fewer hours, but waking at a cycle boundary still tends to beat a longer night cut off mid-cycle. If late nights are the norm, consistency matters more than any single bedtime.

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